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高一英语人教版必修三全册课文_高一英语必修四课文逐句翻译(人教版)

佳句摘抄 编辑: www.shenghbs.com

1、高一英语人教版必修三全册课文

unit 1 festivals around the world festivals and celebrations festivals and celebrations of all kinds have been held everywhere since ancient times. most ancient festivals would celebrate the end of cold weather, planting in spring and harvest in autumn. sometimes celebrations would be held after hunters had caught animals. at that time people would starve if food was difficult to find, especially during the cold winter months. today’s festivals have many origins, some religious, some seasonal, and some for special people or events. festivals of the dead some festivals are held to honour the dead or to satisfy the ancestors, who might return either to help or to do harm. for the japanese festival obon, people should go to clean graves and light incense in memory of their ancestors. they also light lamps and play music because they think that will lead the ancestors back to earth. in mexico, people celebrate the day of the dead in early november. on this important feast day, people eat food in the shape of skulls and cakes with “bones” on them. they offer food, flowers and gifts to the dead. the western holiday halloween also had its origin in old beliefs about the return of the spirits of dead people. it is now a children’s festival, when they can dress up and go to their neighbours’ homes to ask for sweets. if the neighbours do not give any sweets, the children might play a trick on them. festivals to honour people festivals can also be held to honour famous people. the dragon boat festival in china honours the famous ancient poet, qu yuan. in the usa, columbus day is in memory of the arrival of christopher columbus in the new world. india has a national festival on october 2 to honour mohandas gandhi, the leader who helped gain india’s independence from britain. harvest festivals harvest and thanksgiving festivals can be very happy events. people are grateful because their food is gathered for the winter and the agricultural work is over. in european countries, people will usually decorate churches and town halls with flowers and fruit, and will get together to have meals. some people might win awards for their farm produce, like the biggest watermelon or the most handsome rooster. china and japan have mid-autumn festivals when people admire the moon and in china enjoy moon-cakes. spring festivals the most energetic and important festivals are the ones that look forward to the end of winter and to the coming of spring. at the spring festival in china, people eat dumplings, fish and meat and may give children lucky money in red paper. there are dragon dances and carnivals, and families celebrate the lunar new year together. some western countries have very exciting carnivals, which take place forty days before easter, usually in february. these carnivals might include parades, dancing in the streets day and night, loud music and colourful clothing of al kinds. easter is an important religious and social festival for christians around the world. it celebrates the return of jesus from the dead and the coming of spring and new life. japan’s cherry blossom festival happens a little later. the country, covered with cherry tree flowers, looks as though it is covered with pink snow. people love to get together to eat, drink and have fun with each other. festivals let us enjoy life, be proud of our customs and forget our work for a little while.a sad love story li fang was heart-broken. it was valentine’s day and hu jin had said she would meet him at the coffee shop after work. but she didn’t turn up. she could be with her friends right now laughing at him. she said she would be there at seven o’clock, and he thought she would keep her word. he had looked forward to meeting her all day, and now he was alone with his roses and chocolates, like a fool. well, he was not going to hold his breath for her to apologize. he would drown his sadness in coffee. it was obvious that the manager of the coffee shop was waiting for li fang to leave - he wiped the tables, then sat down and turned on the tv - just what li fang needed! a sad chinese story about lost love. the granddaughter of the goddess of heaven visited the earth. her name was zhinü, the weaving girl. while she was on earth she met the herd boy niulang and they fell in love. (“just like me and hu jin,” thought li fang.) they got married secretly, and they were very happy. (“we could be like that,” thought li fang.) when the goddess of heaven knew that her granddaughter was married to a human, she became very angry and made the weaving girl return to heaven. niu lang tried to follow her, but the river of stars, the milky way, stopped him. finding that zhinü was heart-broken, her grandmother finally decided to let the couple cross the milky way to meet once a year. magpies make a bridge of their wings so the couple can cross the river to meet on the seventh day of the seventh lunar month. people in china hope that the weather will be fine on that day, because if it is raining, it means that zhinü is weeping and the couple won’t be able to meet. the announcer said, “this is the story of qiqiao festival. when foreigners hear about the story, they call it a chinese valentine’s story. it’s a fine day today, so i hope you can call all meet the one you love.” as li fang set off for home, he thought, “i guess hu jin doesn’t love me. i’ll just throw these flowers and chocolates away. i don’t want them to remind me of her.” so he did. as he sadly passed the tea shop on the corner on his way home, he heard a voice calling him. there was hu jin waving at him and calling, “why are you so late? i’ve been waiting for you for a long time! and i have a gift for you!” what would he do? he had thrown away her valentine gifts! she would never forgive him. this would not be a happy valentine’s day! unit 2 healthy eating come and eat here (i) wang peng sat in his empty restaurant feeling very frustrated. it had been a very strange morning. usually he got up early and prepared his menu of barbecued mutton kebabs, roast pork, stir-fried vegetables and fried rice. then by lunchtime they would all be sold. by now his restaurant ought to be full of people. but not today! why was that? what could have happened? he thought of his mutton, beef and bacon cooked in the hottest, finest oil. his cola was sugary and cold, and his ice cream was made of milk, cream and delicious fruit. “nothing could be better,” he thought. suddenly he saw his friend li chang hurrying by. “hello, lao li,” he called. “your usual?” but li chang seemed not to hear. what was the matter? something terrible must have happened if li chang was not coming to eat in his restaurant as he always did. wang peng followed li chang into a new small restaurant. he saw a sign at the door. tired of all that fat? want to lose weight? come inside yong hui’s slimming restaurant. only slimming foods served here.make yourself thin again! curiosity drove wang peng inside. it was full of people. the hostess, a very thin lady, came forward. “welcome,” she said. “my name is yong hui. i’ll help you lose weight and be fit in two weeks if you eat here every day.” then she gave a menu to wang peng. there were few choices of food and drink on it: just rice, raw vegetables served in vinegar, fruit and water. wang peng was amazed at this and especially at the prices. it cost more than a good meal in his restaurant! he could not believe his eyes. he threw down the menu and hurried outside. on his way home he thought about his own menu. did it make people fat? perhaps he should go to the library and find out. he could not have yong hui getting away with telling people lies! he had better do some research! at the library wang peng was surprised to find that his restaurant served far too much fat and yong hui’s far too little. even though her customers might get thin after eating yong hui’s food, they were not eating enough energy-giving food to keep them fit. they would become tired very quickly. wang peng felt more hopeful as he drove back home. perhaps with a discount and a new sign he could win his customers back. so he wrote: want to feel fit and energetic? come and eat here! discounts today! our food gives you energy all day! the competition between the two restaurants was on! come and eat here (ii) a week later, wang peng’s restaurant was nearly full and he felt happier. perhaps he would be able to earn his living after all and not have to close his restaurant. he did not look forward to being in debt because his restaurant was no longer popular. he smiled as he welcomed some customers warmly at the door but the smile left his face when he saw yong hui walking in. she did not look happy but glared at him. “may i ask what you were doing in my restaurant the other day? i thought you were a new customer and now i know that you only came to spy on me and my menu,” she shouted. “please excuse me,” he calmly explained, “i wanted to know where all my customers had gone last week. i followed one of them and found them in your restaurant. i don’t want to upset you, but i found your menu so limited that i stopped worrying and started advertising the benefits of my food. why don’t you sit down and try a meal?” yong hui agreed to stay and soon they were both enjoying dumplings and breast of chicken cooked with garlic. when they were served the ice cream, yong hui began to look ill. “i feel sick with all this fat and heavy food,” she said, “i miss my vegetables and fruit.” wang peng was enjoying a second plate of dumplings so he sighed. “yes,” he added, “and i would miss my dumplings and fatty pork. don’t you get tired quickly?” “well, i do have to rest a lot,” admitted yong hui. “but don’t you think it would be better if you were a bit thinner? i’m sure you’d feel much healthier.” they began to talk about menus and balanced diets. “according to my research, neither your restaurant nor mine offers a balanced diet,” explained wang peng. “i don’t offer enough fibre and you don’t offer enough body-building and energy-giving food. perhaps we ought to combine our ideas and provide a balanced menu with food full of energy and fibre.” so that is what they did. they served raw vegetables with the hamburgers and boiled the potatoes rather than fried them. they served fresh fruit with the ice cream. in this way they cut down the fat and increased thefibre in the meal. their balanced diets became such a success that before long wang peng became slimmer and yong hui put on more weight. after some time the two found that their business cooperation had turned into a personal one. finally they got married and live happily ever after. unit 3 the million pound bank note the million pound bank note act i, scene 3 narrator: it is the summer of 1903. two old and wealthy brothers, roderick and oliver, have made a bet. oliver believes that with a million pound bank note a man could survive a month in london. his brother roderick doubts it. at this moment, they see a penniless young man wandering on the pavement outside their house. it is henry adams, an american businessman, who is lost in london and does not know what he should do. roderick: young man, would you step inside a moment, please? henry: who? me, sir? roderick: yes, you. oliver: through the front door on your left. henry: (a servant opens a door) thanks. servant: good morning, sir. would you please come in? permit me to lead the way, sir. oliver: (henry enters) thank you, james. that will be all. roderick: how do you do, mr … er …? henry: adams. henry adams. oliver: come and sit down, mr adams. henry: thank you. roderick: your are an american? henry: that’s right, from san francisco. roderick: how well do you know london? henry: not at all. it’s my first trip here. roderick: i wonder, mr adams, if you mind us asking a few questions? henry: not at all. go right ahead. roderick: may we ask what you’re doing in this country and what your plans are? henry: well, i can’t say that i have any plans. i’m hoping to find work. as a matter of fact, i landed in britain by accident. roderick: how is that possible? henry: well, you see, back home i have my own boat. about a month ago, i was sailing out of the bay … (his eyes stare at what is left of the brothers’ dinner on the table) oliver: well, go on. henry: oh, yes. well, towards nightfall i found myself carried out to sea by a strong wind. it was all my fault. i didn’t know whether i could survive until morning. the next morning i’d just about given myself up for lost when i was spotted by a ship. oliver: and it was the ship that brought you to england. henry: yes. the fact is that i earned my passage by working as an unpaid hand, whichaccounts for my appearance. i went to the american embassy to seek help, but … (the brothers smile at each other) roderick: well, you mustn’t worry about that. it’s an advantage. henry: i’m afraid i don’t quite follow you, sir. roderick: tell us, mr adams, what sort of work did you do in america? henry: i worked for a mining company. could you offer me some kind of work here? roderick: patience, mr adams. if you don’t mind, may i ask how much money you have? henry: well, to be honest, i have none. roderick: (happily) what luck! brother, what luck! (claps his hands together) henry: well, it may seem lucky to you but not to me! on the contrary, in fact. if this is your idea of some kind of joke, i don’t think it’s very funny. (henry stands up to leave) now if you’ll excuse me, i think i’ll be on my way. roderick: please don’t go mr adams. you mustn’t think we don’t care about you. oliver, give him the letter. oliver: yes, the letter. (gets it from a desk and gives it to henry like a gift) the letter. henry: (taking it carefully) for me? roderick: for you. (henry starts to open it) oh, no, you mustn’t open it. not yet. you can’t open it until two o’clock. henry: oh, this is silly. roderick: not silly. there’s money in it. (calls to the servant) james? henry: oh, no. i don’t want your charity. i just want an honest job. roderick: we know you’re hard-working. that’s why we have given you the letter. james, show mr adams out. oliver: good luck, mr adams. henry: well, why don’t you explain what this is all about? roderick: you’ll soon know. (looks at the clock) in exactly an hour and a half. servant: this way, sir. roderick: mr adams, not until 2 o’clock. promise? henry: promise. goodbye. unit 4 astronomy: the science of the stars how life began on the earth no one knows exactly how the earth began, as it happened so long ago. however, according to a widely accepted theory, the universe began with a “big bang” that threw matter in all directions. after that, atoms began to form and combine to create stars and other bodies. for several billion years after the “big bang”, the earth was still just a cloud of dust. what it was to become was uncertain until between 4.5 and 3.8 billion years ago when the dust settled into a solid globe. the earth became so violent that it was not clear whether the shape would last or not. it exploded loudly with fire and rock. they were in time to produce carbon dioxide, nitrogen, water vapour and other gases, which were to make the earth’s atmosphere. what is even more important is that as the earth cooled down, water began to appear on its surface. water had also appeared on other planets like mars but, unlike the earth, it had disappeared later. it was not immediately obvious that water was to be fundamental to the development of life. what many scientists believe is that the continued presence of water allowed the earth to dissolve harmful gases and acids into the oceans and seas. this produced a chain reaction, which made it possible for life to develop. many millions of years later, the first extremely small plants began to appear on the surface of the water. they multiplied and filled the oceans and seas with oxygen, which encouraged the later development of early shellfish and all sorts of fish. next, green plants began to grow on land. they were followed in time by land animals. some were insects. others, called amphibians, were able to live on land as well as in the water. later when the plants grew into forests, reptiles appeared for the first time. they produced young generally by laying eggs. after that, some huge animals, called dinosaurs, developed. they laid eggs too and existed on the earth for more than 140 million years. however, 65 million years ago the age of the dinosaurs ended. why they suddenly disappeared still remains a mystery. this disappearance made possible the rise of mammals on the earth. these animals were different from all life forms in the past, because they gave birth to young baby animals and produced milk to feed them. finally about 2.6 million years ago some small clever animals, now with hands and feet, appeared and spread all over the earth. thus they have, in their turn, become the most important animals on the planet. but they are not looking after the earth very well. they are putting too much carbon dioxide into the atmosphere, which prevents heat from escaping from the earth into space. as a result of this, many scientists believe the earth may become too hot to live on. so whether life will continue on the earth for millions of years to come will depend on whether this problem can be solved. a visit to the moon last month i was lucky enough to have a chance to make a trip into space with my friend li yanping, an astronomer. we visited the moon in our spaceship! before we left, li yanping explained to me that the force of gravity would change three times on our journey and that the first change would be the most powerful. then we were off. as the rocket rose into the air, we were pushed back into our seats because we were trying to escape the pull of the earth’s gravity. it was so hard that we could not say anything to each other. gradually the weight lessened and i was able to talk to him. “why is the spaceship not falling back to the earth? on the earth if i fall from a tree i will fall to the ground.” i asked. “we are too far from the earth now to feel its pull,” he explained, “so we feel as if no gravity at all. when we get closer to the moon, we shall feel its gravity pulling us, but it will not be as strong a pull as the earth’s.” i cheered up immediately and floated weightlessly around in our spaceship cabin watching the earth become smaller and the moon larger. when we got there, i wanted to explore immediately. “come on,” i said. “if you are right, my weight will be less than on the earth because the moon is smaller and i will be able to move more freely. i might even grow taller if i stay here long enough. i shall certainly weigh less!” i laughed and climbed down the steps from the spaceship. but when i tried to step forward. i found i was carried twice as far as on the earth and fell over. “oh dear,” i cried, “walking does need a bit of practice now that gravity has changed.” after a while i got the hang of it and we began to enjoy ourselves. leaving the moon’s gravity was not as painful as leaving the earth’s. but returning to the earth was very frightening. we watched, amazed as fire broke out on the outside of the spaceship as the earth’s gravity increased. again we were pushed hard into our seats as we came back to land. “that was very exhausting but very exciting too,” i said. “now i know much more about gravity! do you think we could visit some stars next time?” “of course,” he smiled, “which star would you like to go to?”

2、高一英语必修四课文逐句翻译(人教版)

1.必修四unit1a student of african wildlife 非洲野生动物研究者 it is 5:45 am and the sun is just rising over gombe national park in east africa. 清晨5点45分,太阳刚从东非的贡贝国家公园的上空升起, following jane's way of studying chimps, our group are all going to visit them in the forest. 我们一行人准备按照简研究黑猩猩的方法去森林里拜访它们。 jane has studied these families of chimps for many years and helped people understand how much they behave like humans. 简研究这些黑猩猩家族已经很多年了,她帮助人们了解黑猩猩跟人类的行为是多么的相似。watching a family of chimps wake up is our first activity of the day. 我们当天的首项任务就是观察黑猩猩一家是如何醒来的。this means going back to the place where we left the family sleeping in a tree the night before. 这意味着我们要返回前一天晚上我们离开黑猩猩一家睡觉的大树旁。everybody sits and waits in the shade of the trees while the family begins to wake up and move off. 大家坐在树荫下等待着,这时候猩猩们睡醒了,准备离开。 then we follow as they wander into the forest. 然后这群黑猩猩向森林深处漫步而去,我们尾随其后。most of the time, chimps either feed or clean each other as a way of showing love in their family. 在大部分时间里,黑猩猩或相互喂食,或彼此擦身,这在它们的家庭里是表示爱的方式。 jane warns us that our group is going to be very tired and dirty by the afternoon and she is right. 简预先提醒我们,到下午的时候我们就会又脏又累。她说对了。however, the evening makes it all worthwhile. 不过到傍晚时分我们觉得这一切都是值得的。 we watch the mother chimp and her babies play in the tree. then we see them go to sleep together in their nest for the night. 我们看到黑猩猩妈妈跟她的幼子们在树上玩耍,后来看见它们晚上一起回窝里睡觉了。we realize that the bond between members of a chimp family is as strong as in a human family. 我明白了猩猩家庭成员之间的联系像人类家庭一样紧密。 nobody before jane fully understood chimp behaviour. 在简之前没有人完全了解黑猩猩的行为。 she spent years observing and recording their daily activities. 她花了多年的时间来观察并记录黑猩猩的日常生活。 since her childhood she had wanted to work with animals in their own environment. 从孩童时代起,简就想在动物生活的环境中研究它们。however, this was not easy. 但是,这不是一件简单的事。when she first arrived in gombe in 1960, it was unusual for a woman to live in the forest. 当她1960年最初来到贡贝时,对女性来说,住进大森林还是很稀罕的事情。only after her mother came to help her for the first few months was she allowed to begin her project. 她母亲头几个月来帮过她的忙,这才使她得以开始自己的计划。her work changed the way people think about chimps. 她的工作改变了人们对黑猩猩的看法。 for example, one important thing she discovered was that chimps hunt and eat meat. 比方说,她的一个重要发现是黑猩猩猎食动物。until then everyone had thought chimps ate only fruit and nuts. 在此之前,人们一直认为黑猩猩只吃水果和坚果。 she actually observed chimps as a group hunting a monkey and then eating it. 而她曾经亲眼看到过一群黑猩猩捕杀一只猴子,然后把它吃掉。 she also discovered how chimps communicate with each other, and her study of their body language helped her work out their social system.她还发现了黑猩猩之间是如何交流的,而她对黑猩猩肢体语言的研究帮助她勾勒出黑猩猩的社会体系。 for forty years jane goodall has been outspoken about making the rest of the world understand and respect the life of these animals. 40年来,简∙古道尔一直在呼吁世人了解并尊重这些动物的生活。 she has argued that wild animals should be left in the wild and not used for entertainment or advertisements. 她主张应该让野生动物留在野外生活,而不能用于娱乐或广告。 she has helped to set up special places where they can live safely. 她还为黑猩猩建起了可以安全生活的保护区。she is leading a busy life but she says: 她的生活是忙忙碌碌的,然而,正如她所说的:"once i stop, it all comes crowding in and i remember the chimps in laboratories. it's terrible. ―我一旦停下来,所有的一切都会涌上心头。我就会想起实验室的黑猩猩,太可怕了。 it affects me when i watch the wild chimps. 每当我看着野生黑猩猩时,这个念头总是萦绕着我。i say to myself, 'aren't they lucky?" 我会对自己说:‗难道它们不幸运吗?‘ and then i think about small chimps in cages though they have done nothing wrong. 然后我就想起那些没有任何过错却被关在笼子里的小黑猩猩。once you have seen that you can never forget ..."一旦你看到这些,你就永远不会忘记……‖ she has achieved everything she wanted to do: working with animals in their own environment, gaining a doctor's degree and showing that women can live in the forest as men can. 简已经得到了她想要得到的一切:在动物的栖息地工作;获得博士学位;还向世人证明女人和男人一样也能在森林里生活。she inspires those who want to cheer the achievements of women.她激励着人们为妇女们的成就而欢呼喝彩。 2.必修四unit 1 why not carry on her good work? 为什么不继续她的事业? i enjoyed english, biology, and chemistry at school, but which one should i choose to study at university? 上学时我喜欢英语、生物和化学,但是我进大学该选哪门专业呢?i did not knowthe answer until one evening when i sat down at the computer to do some research on great women of china. 直到有一天晚上坐在电脑旁研究中国的伟大女性时,我才有了答案。 by chance i came across an article about a doctor called lin qiaozhi, a specialist in women's diseases. 很偶然地,我看到了一篇关于林巧稚大夫的文章。她是妇科专家,she lived from 1901 to 1983. 1901年出生,1983年去世。 it seemed that she had been very busy in her chosen career, travelling abroad to study as well as writing books and articles. 林巧稚似乎一直都在为自己选择的事业而奔忙,她去国外留学,并写了很多书和文章。one of them caught my eye. 其中有一本书引起了我的注意。it was a small book explaining how to cut the death rate from having and caring for babies. 这是一本小书,介绍如何从妇女怀孕到护理婴儿的过程中降低死亡率。she gave some simple rules to follow for keeping babies clean, healthy and free from sickness. 她提出了一些可以遵循的简单的做法,保持婴儿清洁和健康,让他们远离疾病。 why did she write that? 她为什么要写这些东西呢? who were the women that lin qiaozhi thought needed this advice? 林巧稚认为哪些妇女会需要这些忠告呢? i looked carefully at the text and realized that it was intended for women in the countryside. 我细细地看了这篇文章,了解到那是为农村妇女写的。perhaps if they had an emergency they could not reach a doctor.也许是她们在遇到紧急情况时找不到医生。 suddenly it hit me how difficult it was for a woman to get medical training at that time. 突然我想起,在那个年代,一个女子去学医是多么困难啊!that was a generation when girls' education was always placed second to boys'. 那可是一个女性受教育总是排在男性之后的年代。 was she so much cleverer than anyone else? 难道她比别人要聪明得多? further reading made me realize that it was hard work and determination as well as her gentle nature that got her into medical school. 进一步阅读使我了解到,是苦干、决心和善良的天性使她走进医学院的大门。what made her succeed later on was the kindness and consideration she showed to all her patients. 后来使她成功的是她对所有病人献出的爱心和体贴。there was story after story of how lin qiaozhi, tired after a day's work, went late at night to deliver a baby for a poor family who could not pay her.数不胜数的故事讲述着林巧稚如何在劳累一天之后,又在深夜去为贫苦家庭的产妇接生,而这些家庭是不可能给她报酬的。 by now i could not wait to find out more about her. 现在我迫不及待地想多了解一些有关她的情况。 i discovered that lin qiaozhi had devoted her whole life to her patients and had chosen not to have a family of her own. 我发现林巧稚把毕生都奉献给了病人,而自己却选择了独身。instead she made sure that about 50,000 babies were safely delivered. 她确保了大约五万名婴儿的安全出生。by this time i was very excited. 这时候,我非常激动。why not study at medical college like lin qiaozhi and carry on her good work? 为什么不像林巧稚那样去读医学院,继续她高尚的事业呢?it was still not too late for me to improve my studies, prepare for the university entrance examinations, and…. 现在努力提高学习成绩、准备大学入学考试还不算晚…… 3.必修四unit2 a pioneer for all people造福全人类的先驱者 although he is one of china's most famous scientists, yuan longping considers himself a farmer, for he works the land to do his research. 尽管是中国最的科学家之一,袁隆平仍然认为自己是个农民,因为他在田里耕作,进行科学研究。indeed, his sunburnt face and arms and his slim, strong body are just like those of millions of chinese farmers, for whom he has struggled for the past five decades. 的确,他被太阳晒得黝黑的脸庞和和手臂,以及他那瘦削而又结实的身躯,就跟其他千百万中国农民一样,过去50年来,他一直在努力帮助他们。dr yuan longping grows what is called super hybrid rice. 袁博士种植的是被称为―超级杂交水稻的‖的稻种。 in 1974, he became the first agricultural pioneer in the world to grow rice that has a high output. 1974年,他成为世界上第一位种植高产水稻的农业先锋。this special strain of rice makes it possible to produce one-third more of the crop in the same fields. 这种特殊的稻种使得同样的田地多收获三分之一的产量。now more than 60% of the rice produced in china each year is from this hybrid strain.如今中国每年出产的稻米有60%以上出自这种杂交稻种。 born in a poor farmer's family in 1930, dr yuan graduated from southwest agricultural college in 1953. 袁博士1930年出生,1953年毕业于西南农学院。since then, finding ways to grow more rice has been his life goal. 从那时起,找到水稻高产的方法就成为他一生的目标。as a young man, he saw the great need for increasing the rice output. 年轻时,他就看到了稻田增产的巨大需求。 at that time, hunger was a disturbing problem in many parts of the countryside. 当时,饥荒是许多农村地区面临的严重问题。dr yuan searched for a way to increase rice harvests without expanding the area of the fields. 袁博士要在不增加土地面积的基础上寻求达到增收稻谷的途径。 in 1950, chinese farmers could produce only fifty million tons of rice. 1950年,中国农民只能生产五千万吨稻谷, in a recent harvest, however, nearly two hundred million tons of rice was produced. 而近来却生产了将近两亿吨稻谷。these increasedharvests mean that 22% of the world's people are fed from just 7% of the farmland in china. 这一粮食产量的增加意味着中国仅仅7%的耕地养活了世界22%的人口。 dr yuan is now circulating his knowledge in india, vietnam and many other less developed countries to increase their rice harvests. 袁博士现在在印度、越南和很多其他欠发达国家传播提高水稻产量的知识。 thanks to his research, the un has more tools in the battle to rid the world of hunger. 多亏了他的研究,联合国在消除世界饥饿的战斗中有了更多的办法。using his hybrid rice, farmers are producing harvests twice as large as before. 用他的杂交水稻种子,农民种出的粮食比以前多了一倍。 dr yuan is quite satisfied with his life. 袁博士很满意他的生活。however, he doesn't care about being famous. he feels it gives him less freedom to do his research. 但是,他对成名并不在意,并且觉得出名后搞科研就不那么自由了。 he would much rather keep time for his hobbles. 他宁愿把时间花在自己的业余爱好上。he enjoys listening to violin music, playing mah-jong, swimming and reading. 他喜欢听小提琴乐曲、打麻将、游泳和读书。spending money on himself or leading a comfortable life also means very little to him. 在自己身上花钱或者享受舒适的生活对袁博士来说意义不大。indeed, he believes that a person with too much money has more rather than fewer troubles. 事实上,他认为一个人有了太多钱,他的麻烦事只会更多,而不是更少。 he therefore gives millions of yuan to equip others for their research in agriculture. 于是,他拿出好几百万元帮助其他人进行农业科学研究。 just dreaming for things, however, costs nothing. 梦想是不花本钱的。 long ago dr yuan had a dream about rice plants as tall as sorghum. each ear of rice was as big as an ear of corn and each grain of rice was as huge as a peanut. 很久以前,袁博士曾在梦里看到水稻长得像高粱一样高,稻穗跟玉米穗一样大,而每粒稻谷像花生米一样大。 dr yuan awoke from his dream with the hope of producing a kind of rice that could feed more people. 袁博士从梦中醒来,希望能种植一种能养活更多人的水稻。now, many years later, dr yuan has another dream: to export his rice so that it can be grown around the globe. 在很多年后的今天,袁博士还有另外一个梦想,那就是他的稻谷可以出口并长遍全球。one dream is not always enough, especially for a person who loves and cares for his people.一个梦想总是不够的,尤其对一个热爱和关心人民的人来说更是如此。 4.必修四unit2 chemical or organic farming? 化学耕作还是有机耕作? over the past half century, using chemical fertilizers has become very common in farming. 在过去的半个世纪里,在耕作中使用化肥已经非常普遍。many farmers welcomed them as a great way to stop crop disease and increase production. 很多农民喜欢使用化肥。把化肥作为防治农作物病虫害和提高产量的重要手段。 recently, however, scientists have been finding that long-term use of these fertilizers can cause damage to the land and, even more dangerous, to people's health. 然而,最近科学家发现长期使用这些肥料会造成土地受损,甚至更危险的是,会对人们的健康造成危害。 what are some of the problems caused by chemical fertilizers? 化肥带来的问题有哪些呢? first, they damage the land by killing the helpful bacteria and pests as well as the harmful ones. 首先,化肥在杀死病菌和害虫的同时也会杀死有益的细菌和昆虫,从而破坏土地。chemicals also stay in the ground and underground water for a long time. 化学物质还会在地里和地下水中保存很长时间,this affects crops and, therefore, animals and humans, since chemicals get inside the crops and cannot just be washed off. 而这会影响到庄稼,进而影响到动物和人类,因为化学成分会进入到农作物中,并且不能被冲洗掉。these chemicals in the food supply build up in people's bodies over time. 随着时间的推移,食物中的这些化学成分会在人体中堆积。many of these chemicals can lead to cancer or other illnesses. 很多化学成分能导致癌症或其他疾病。 in addition, fruit, vegetables and other food grown with chemical fertilizers usually grow too fast to be full of much nutrition. 另外,施过化肥的水果、蔬菜和其他食物通常生长得过快而营养不足。 they may look beautiful, but inside there is usually more water than vitamins and minerals. 它们表面上很好看,但里面通常是含过多的水分,而不是维生素和矿物质。 with these discoveries, some farmers and many customers are beginning to turn to organic farming. 由于这些发现,一些农民和消费者开始转向有机耕作。 organic farming is simply farming without using any chemicals. 有机耕作就是不用任何化学肥料的耕作。they focus on keeping their soil rich and free of disease. 农民关心的是保持土壤肥沃并且免受病害。 a healthy soil reduces disease and helps crops grow strong and healthy. 健康的土壤会减少病虫害并且帮助农作物茁壮成长。 organic farmers, therefore, often prefer using natural waste from animals as fertilizer. 因此,有机耕作的农民通常喜欢把天然的动物粪便当作肥料。 they feel that this makes the soil in their fields richer in minerals and so more fertile. 他们认为这样会使地里的土壤更富含矿物质,因而也会更加肥沃, this also keeps the air, soil, water and cropsfree from chemicals.同时还可以让空气、土壤、水以及农作物不受化学物质的污染。 organic farmers also use many other methods to keep the soil fertile. 有机耕作的农民也使用很多其他的方法来保持土地肥沃。they often change the kind of crop in each field every few years, for example, growing corn or wheat and then the next year peas or soybeans. 在同一块地里,他们经常每隔几年就换种农作物。 例如,种玉米和小麦后来年再改种豌豆或大豆。 crops such as peas or soybeans put important minerals back into the soil, making it ready for crops such as wheat or corn that need rich and fertile soil. 像豌豆或大豆这样的农作物将重要的矿物质带回土壤,从而使之适宜于种植要求土地肥沃的农作物,比如玉米或小麦。 organic farmers also plant crops to use different levels of soil, for example, planting peanuts that use the ground's surface followed by vegetables that put down deep roots. 有机耕作的农民还种植多种农作物来利用不同层次的土壤。比如,他们先种植生长于浅层土壤的花生,然后再种植生根于深层土壤的蔬菜。some organic farmers prefer planting grass between crops to prevent wind or water from carrying away the soil, and then leaving it in the ground to become a natural fertilizer for the next year's crop还有一些有机耕作者喜欢在农作物之间种草,以防止水土流失,并且把草留在地里,从而成为来年农作物的天然肥料。 these many different organic farming methods have the same goal: to grow good food and avoid damaging the environment or people's health. 这些不同的有机耕作的方法有着同样的目标:种植好的粮食,避免损害环境或者人们的健康。 5.必修四unit 3 a master of nonverbal humour无声的幽默的大师 as victor hugo once said, "laughter is the sun that drives winter from the human face",维克多·雨果曾经说过:―笑容如同阳光,驱散人们脸上的阴霾‖and up to now nobody has been able to do this better than charlie chaplin. 关于这一点,直到今天也没有人比查理·卓别林做的更好。 he brightened the lives of americans and british through two world wars and the hard years in between. 在两次世界大战及中间艰苦的岁月里,他给英国和美国人民带来了快乐。he made people laugh at a time when they felt depressed, so they could feel more content with their lives. 在人们感到沮丧的时候,查理使人们开怀大笑,于是他们对自己的生活感到更加满足。 not that charlie's own life was easy! 然而卓别林自己的生活也并不容易。he was born in a poor family in 1889. his parents were both poor music hall performers. 他生于1889年,出身贫寒。他的父母都是杂耍戏院里贫穷的演员。you may find it astonishing that charlie was taughtto sing as soon as he could speak and dance as soon as he could walk. 你可能会感到惊奇,查理刚会说话时大人就教他唱歌,他刚会走路时大人就教他跳舞。 such training was common in acting families at this time, especially when the family income was often uncertain. 这样的训练在当时的演员家庭中是很普遍的,尤其是在家庭收入经常不稳定的时候。 unfortunately his father died, leaving the family even worse off, so charlie spent his childhood looking after his sick mother and his brother. 不幸的是他的父亲去世了,使得他的家庭更加艰难,所以查理在童年时期就要照顾生病的母亲和弟弟。 by his teens, charlie had, through his humour, become one of the most popular child actors in england. 在十多岁的时候,凭借着自己的幽默,查理已经在英国成为欢迎的童星之一。 he could mime and act the fool doing ordinary everyday tasks. 他能够不说话而仅靠动作来模仿傻子做日常的任务。no one was ever bored watching him -his subtle acting made everything entertaining. 看他的表演没有人会感到无聊——他巧妙的表演使得一切都那么滑稽可笑。 as time went by, he began making films. .随着时间的推移,他开始拍电影。he grew more and more popular as his charming character, the little tramp, became known throughout the world. 他塑造的可爱的―小流浪汉‖角色开始闻名于世,而查理越来越受欢迎。the tramp, a poor, homeless man with a moustache, wore large trousers, worn-out shoes and a small round black hat. he walked around stilly carrying a walking stick. 这个穷苦的无家可归的小流浪汉,留着小胡子,穿着大裤子、破鞋子,头顶着黑色的小圆帽。他手里拿着一根手杖迈着僵硬的步伐四处走动。 this character was a social failure but was loved for his optimism and determination to overcome all difficulties. 这个角色是个社会生活中的失败者,但他乐观的精神和战胜困难的决心使他受到人们的喜爱。 he was the underdog who was kind even when others were unkind to him. 面对并不善待他的人,这个弱者依然保持友善的态度。 how did the little tramp make a sad situation entertaining? 然而这个小流浪汉是如何把悲凉的遭遇变得滑稽可笑的呢? here is an example from one of his most famous films, the gold rush. 这里有一个例子,来自于他最的电影之一《淘金记》。 it is the mid-nineteenth century and gold has just been discovered in california. 19世纪中叶,在加利福尼亚州发现了金子。 like so many others, the little tramp and his friend have rushed there in search of gold, but without success. 像其他很多人一样,小流浪汉和他的朋友也涌向那里去淘金,但却没有成功。instead they are hiding in a small hut on the edge of a mountain during a snowstorm with nothing to eat. 相反,他们被暴风雪困在山边的一个小木屋中,没有任何东西可吃。 they areso hungry that they try boiling a pair of leather shoes for their dinner. 他们饿极了,只好煮了一双皮鞋来充饥。 charlie first picks out the laces and eats them as if they were spaghetti. 查理首先挑出鞋带来吃,像吃意大利面条一样。then he cuts off the leather top of the shoe as if it were the finest steak. 然后他把皮鞋上端的皮子切下来,就像切下一块的牛排。 finally he tries cutting and chewing the bottom of the shoe. 最后他试着把鞋底割下来嚼着吃。he eats each mouthful with great enjoyment. 他每一口都嚼得津津有味。 the acting is so convincing that it makes you believe that it is one of the best meals he has ever tasted! 查理的表演是那么有说服力,以至于你会相信这顿饭是他所吃过的最美味的一餐! charlie chaplin wrote, directed and produced the films he starred in. 查理·卓别林自编、自导、自制他主演的电影。in 1972 he was given a special oscar for his outstanding work in films. 1972年他被授予奥斯卡特别奖,以表彰他在电影界的杰出工作。he lived in england and the usa but spent his last years in switzerland, where he was buried in 1977.他生活在英国和美国,却在瑞士度过了生命中最后的日子,并于1977年安葬在那里。he is loved and remembered as a great actor who could inspire people with great confidence人们热爱和怀念这位伟大的演员,因为他鼓舞人们并增强他们的信心。

3、人教版高二生物必修三全册教案

以下是为大家整理的关于《人教版高二生物必修三全册教案》,供大家学习参考!

录第1章 人体的内环境与稳态 ………………………………………………………… 1第1节 细胞生活的环境………………………………………………………………… 1第2节 内环境稳态的重要性…………………………………………………………… 4第2章 动物和人体生命活动的调节 ………………………………………………… 9第1节 通过神经系统的调节…………………………………………………………… 9

第2节 通过激素的调节…………………………………………………………………11

第3节 神经调节与体液调节的关系……………………………………………………15第4节 免疫调节…………………………………………………………………………17第3章 植物的激素调节…………………………………………………………………19

第1节 植物生长素的发现………………………………………………………………19

第2节 生长素的生理作用………………………………………………………………21第3节 其他植物激素……………………………………………………………………24第4章 种群和群落 ………………………………………………………………………25

第1节 种群的特征………………………………………………………………………26

第2节 种群数量的变化…………………………………………………………………29

第3节 群落的结构………………………………………………………………………33第4节 群落的演替………………………………………………………………………35第5章 生态系统及其稳定性……………………………………………………………37

第1节 生态系统的结构…………………………………………………………………37

第2节 生态系统的能量流动……………………………………………………………39

第3节 生态系统的物质循环……………………………………………………………41

第4节 生态系统的信息传递……………………………………………………………43第5节 生态系统的稳定性………………………………………………………………44第6章 生态环境的保护…………………………………………………………………46

第1节 人口增长对生态环境的影响……………………………………………………46

第2节 保护我们共同的家园……………………………………………………………47

第1章人体的内环境与稳态第1节 细胞生活的环境教学目标1. 知识方面1.描述内环境的组成和理化性质。2.说明内环境是细胞与外界环境进行物质交换的媒介。3.尝试建构人体细胞与外界环境的物质交换模型。2态度观念方面 通过内环境稳态的基本知识的学习,使学生明确只有通过各器官系统的协调活动,才能实现内环境的稳态,从而使学生逐步树立生物体的局部与整体相统一的辩证唯物主义观点.3.能力方面通过缓冲物质的调节作用和水平平衡调节实例的讨论分析,使学生进一步理解稳态的生理意义,并提高运用学到的生物学知识评价和解决实际问题的能力.重点、难点分析重点:1)内环境的组成和理化性质。(2)内环境是细胞与外界环境进行物质交换的媒介。. 难点:(1)内环境的理化性质。(2)内环境是细胞与外界环境进行物质交换的媒介

内环境稳态的概念即是本课题的重点内容,也是一个难点内容,建议结合学生的认知规律逐层推进.首先,以人体为例,结合初中已掌握的知识,让学生弄懂由血浆、组织液、淋巴构成的人体内环境及三个成分之间的相互关系,并且明确:体内细胞只有通过内环境,才能与外界环境进行物质交换.然后结合人们的日常生活分析实例,证明当内环境的理化性质发生变化时,机体在神经系统和体液的调节下,通过各器官系统的协调活动,能够维持内环境的稳态,进而归纳出内环境稳态的概念,并且使学生认识到:当内环境的稳态遭到破坏时,就会引起代谢紊乱并导致疾病。教学模式启发、讲解、讨论结合式。教学手段课件、实物投影仪。教学过程设计一、 参考课时一课时二、 设计思路细胞生活的环境教学目标2. 知识方面(1) 明确内环境的概念及组成环境的三种成分之间的关系;(2) 理解体内细胞物质交换是通过内环境而实现的;(3) 理解内环境稳态的概念及其生物意义.2态度观念方面 通过内环境稳态的基本知识的学习,使学生明确只有通过各器官系统的协调活动,才能实现内环境的稳态,从而使学生逐步树立生物体的局部与整体相统一的辩证唯物主义观点.3.能力方面通过缓冲物质的调节作用和水平平衡调节实例的讨论分析,使学生进一步理解稳态的生理意义,并提高运用学到的生物学知识评价和解决实际问题的能力.重点、难点分析

重点:内环境稳态的概念及其生物意义.

难点:内环境稳态的概念.

内环境稳态的概念即是本课题的重点内容,也是一个难点内容,建议结合学生的认知规律逐层推进.首先,以人体为例,结合初中已掌握的知识,让学生弄懂由血浆、组织液、淋巴构成的人体内环境及三个成分之间的相互关系,并且明确:体内细胞只有通过内环境,才能与外界环境进行物质交换.然后结合人们的日常生活分析实例,证明当内环境的理化性质发生变化时,机体在神经系统和体液的调节下,通过各器官系统的协调活动,能够维持内环境的稳态,进而归纳出内环境稳态的概念,并且使学生认识到:当内环境的稳态遭到破坏时,就会引起代谢紊乱并导致疾病。教学模式启发、讲解、讨论结合式。教学手段课件、实物投影仪。教学过程设计一、 参考课时一课时二、 设计思路内环境稳态是机体进行正常生命活动的必要条件. 要想讲透这个问题,首先就要弄清内环境的概念.和外界环境相比较,内环境看不见,摸不着,比较抽象.因此,在设计本课时,利用了一个课件,借助计算机,变抽象为具体,使学生充分认识内环境的构成和作用.内环境的稳态是本课的重点和难点.首先让学生清楚内环境稳态时各组分的理化指标,从宏观上有一个认识,再分析具体事例,说明这些指标在 一定的范围内变化,而不会影响正常的生命活动.再分析事例过程中,充分利用学生已有的生物学和化学知识,调动学生学习的主动性,发挥学生的主体作用.为了更明确地说明内环境稳态的意义,利用投影仪,将由于内环境稳态被破坏而出现的一些病症展现给学生.最后以一道习题作为知识的巩固和反馈.三、 教学过程1. 复习提问:(1)动物的新陈代谢与植物新陈代谢有何显著不同?(2)单细胞动物是何进行物质交换的?2导入:在学生讨论回答的基础上,教师指出:组成人和动物体的细胞数以亿计,其中绝大多数细胞不能直接与外界环境接触,那么这些与外界环境隔离的体内细胞生活在什么样的环境中?它们是怎样与外界环境进行物质交换的呢?引出内环境的知识.3.什么是内环境?(1)明确体液的组成人体内含有大量的液体,统称为体液(成人体液总量约占体重的65%左右).体液构成概括如下: 细胞内液体液 血浆 细胞外液 组织液 淋巴教师需给学生指出的是:体液是由水﹑无机盐﹑低分子有机物和蛋白质构成的.除蛋白质外,其他成分均可通过毛细血管壁,从而为弄清下面的问题奠定基础.(2)明确血浆﹑组织液和淋巴三者之间的关系.课件参考教材图3–15首先使学生明确血浆﹑组织液和淋巴存在的位置:血浆—血液的液体部分,存在与血管中;组织液—组织间隙的液体;淋巴—毛细淋巴管内形成.然后动态显示三者之间的关系:(1)细胞浸浴在组织液中,在细胞内液 与组织液之间只隔着细胞膜,水分和一切能够透过细胞膜的物质,都可以在细胞内液与组织液之间进行交换.(2)在组织液与血浆之间只隔着毛细血管壁,水分和一切能够透过毛细血管壁的物质,都可以在两者之间进行交换.(3)组织液还可以渗入毛细淋巴管形成淋巴.教师需给学生指出:毛细淋巴管比壁细胞呈覆瓦状(鱼鳞状)排列,组织液中的大部分成分可以渗入毛细淋巴管形成淋巴,而淋巴不能反渗回组织液.淋巴经淋巴循环,由胸导管和右侧淋巴管进入左右琐骨下的静脉,又回到血液中.总结三者关系如下:通过上述讲解得出结论:人体内细胞外液,构成了人体内细胞生活的液体环境,才能与外界环境进行物质交换.教师需给学生指出:内环境的“内”和“外”是相对的,从细胞角度看问题就是细胞外液,从人体的角度看问题,就是内环境.根据上面所讲内容,学生讨论总结:与人体内细胞进行物质交换有直接关系的系统有哪些? 投影仪显示下表:当血浆流经毛细血管时,水和一切能够透过毛细血管壁的物质可以在毛细血管动脉端渗出,进入组织细胞间隙而成为组织液,绝大多数的组织液在毛细血管静脉端又可以重新渗入血浆中。少量的组织液还可以渗入毛细淋巴管,形成淋巴,淋巴经淋巴循环由左右锁骨下静脉汇入血浆中。它们之间的关系如图1-2所示。由此可见,全身的细胞外液是一个有机的整体。 图1-2 组织液、血浆、淋巴之间的关系内环境的理化性质是一个更为抽象、更难以理解的深层次问题。一般的讲解难以在学生的头脑中留下深刻印象。可以引导学生开展资料分析、实验现象分析等讨论活动,使学生理解这部分内容。在资料分析中,5个讨论题是为学生自学课本内容设计的,讨论题1和2围绕有关细胞外液成分的问题;讨论题3和4与细胞外液的渗透压和酸碱度有关;讨论题5与内环境是细胞与外界环境进行物质交换的媒介有关。要让每个学生独立完成这5个题的讨论是有一定难度的,因此教师应根据实际情况,针对不同的学生,采用不同的教学策略。例如,如果学生基础较好、能力较强,可以把他们分成小组,提供充足的时间,放手让他们讨论,并自学课本上的相关内容,最后由教师进行简单总结。对于基础较差和能力较弱的学生,教师宜给予适当的引导,再根据教学进程安排学生分阶段进行讨论。如学习细胞外液成分时,先讨论1、2题,学习渗透压和酸碱度时,再讨论3、4题,第5题则可以放到“内环境与外界环境进行物质交换”标题下的“思考与讨论”中去。这样做有利于分散难点,突破每一阶段的重点。3.以任务驱动讨论的开展,以讨论促进任务的完成,通过建立与已有知识的联系,最终实现对“内环境是细胞与外界环境进行物质交换的媒介”的充分理解。这部分教学内容与学生在必修1中学过的物质出入细胞的内容,及初中学过的消化、呼吸、循环、泌尿系统等知识联系紧密。教材提供了“思考与讨论”和“技能训练”两项学生活动,旨在通过活动引导学生回忆学过的相关知识,并建立起与新知识间的联系,从而理解内环境是细胞与外界环境进行物质交换的媒介。教学时,建议将“技能训练”作为一项任务布置给学生,要求每一位学生利用课下的时间独立完成。学生在接受任务后,会开始思考自己应该如何完成这项任务。他们可能会面临两个问题:一是人体细胞与外界环境的物质交换过程是如何完成的?二是选择哪种表现形式来表达。这时他们就会产生与他人交流的愿望。老师可提出,为了帮助同学降低完成任务的难度,同时保证任务完成的质量,要求同学以小组为单位,在课堂上就自己面临的问题开展讨论,也可根据“思考与讨论”中的问题展开讨论。由于学生是带着任务参与讨论的,因此会很投入、很积极,讨论的效果就能得到保证。讨论结束后,应由同学或老师总结人体细胞与外界环境进行物质交换的过程,这样可以帮助学生扫清知识上的障碍,为课下完成任务奠定基础。同时,提供给学生一个制作好的范例,如图解(见图1-1)或课件,使学生明确这项任务的要求,即制作时首先要注意科学性,其次要注意形式的多样化。在指导学生完成任务的过程中还应发挥评价的作用,促进学生积极地、高质量地完成任务。例如,学生完成任务后,教师要给予及时评价,成绩可以记入学期总评,或选出优秀作品在课堂展示、交流、点评等。 图1-1 体内细胞与外界环境进行物质交换的过程练习:p6 一、基础题 二、拓展题课后反思第2节 内环境稳态的重要意义教学目标一.知识方面1.说明内环境稳态及其生理意义;2.简述稳态的调节机制。3.关注内环境稳态与健康的关系。二.态度观念方面 通过内环境稳态的基本知识的学习,使学生明确只有通过各器官系统的协调活动,才能实现内环境的稳态,从而使学生逐步树立生物体的局部与整体相统一的辩证唯物主义观点.三.能力方面通过稳态的调节机制的调节作用和体温平衡调节实例的讨论分析,使学生进一步理解稳态的生理意义,并提高运用学到的生物学知识评价和解决实际问题的能力.重点、难点分析

重点:内环境稳态的概念及其生物意义.

难点:内环境稳态的概念.

教学模式 启发、讲解、讨论结合式。教学手段 课件、实物投影仪。教学过程设计参考课时 一课时设计思路说明:本节内容的教学是按照教材顺序安排的,采用先授课后实验的模式。本案例的设计针对课堂授课部分。 三、教学实施的程序学生活动 教师的组织和引导 教学意图课下完成调查。 上次课结束前布置作业:按照课本上的要求完成“体温日变化规律”的调查。 学生体验体温的相对稳定情况。学生汇报调查结果,回答问题。 请同学汇报体温调查的结果,并根据调查结果回答下面的问题:1.同一个人在一日内的体温变化有何特点?2.不同的人(年龄、性别不同)体温变化有何异同?3.人体温的日变化与当地气温的日变化有何差异?总结:健康人的体温始终接近37 ℃,处于动态平衡中。 讲述:像体温的变化情况一样,健康人内环境的每一种成分和理化性质都处于动态平衡之中,这种动态平衡称之为稳态,内环境的稳定是机体进行正常生命活动的必要条件。这节课我们一起来学习“第2节 内环境稳态的重要性”。 引出本节课的课题。 学生尝试列举事实。 体温是内环境理化性质的一个方面,调查结果证明体温处于动态平衡中。那么有哪些事实可以证明内环境的ph和渗透压也处于动态平衡中呢? 启发学生思考回忆已有知识。 学生观察,回答问题:甲试管中血浆ph变化不明显;乙试管中水的ph变化明显。可见血浆ph处于动态平衡中。 下面我们首先来观察一个演示实验。教师演示实验过程,引导学生观察实验现象。取甲乙两个洁净试管,向甲内加入血浆,乙内加入等量蒸馏水,用ph试纸检测。然后,向甲、乙内各滴入等量的几滴hcl或naoh,摇匀后,再用ph试纸检测。教师展示实验结果,提问:甲、乙两支试管在加入酸或碱后的ph变化有何不同?由此可以得出什么结论? 说明人体内环境的ph处于动态平衡中,培养学生的观察能力、分析实验现象得出实验结果的能力。学生举例说明:多饮多尿、输液必须输生理盐水等。 内环境的理化性质除温度、酸碱度外,还有渗透压,内环境的渗透压是否也处于动态平衡中呢?请同学举例说明。 启发学生联系生活经验,理解渗透压的稳定。学生回答(答案略),可能回答不够准确,教师要及时补充。 内环境中的化学成分是如何变化的呢?出示课本“问题探讨”中的血液生化六项检查化验单。先说明各检查项目与健康状况的关系,然后提问:1.每种成分的参考值(正常值)都有一个变化范围,这说明什么?2.从化验单上看,每种成分的指标是否正常? 让学生学会阅读化验单;说明内环境化学成分处于动态平衡中。学生总结稳态概念。 根据以上内容,引导学生总结稳态概念。教师强调:(1)稳态不是恒定不变,而是相对恒定的一种动态变化;(2)这种动态变化保持在一定范围内。简要介绍稳态概念的提出和发展,并说明稳态概念已成为生命科学的一大基本概念(详细内容可参考教材中的“科学史话”)。 学生边展示、边讲解。 内环境稳态是怎样实现的呢?下面以内环境中的营养物质、代谢废物、02、c02等化学成分为例来分析。请学生利用自己制作的课件或图解,回顾内环境中的营养物质、代谢废物、02、c02等化学成分的来源与去路。说明这些成分要保持相对稳定,首先与消化、呼吸、循环、泌尿等系统的功能及细胞代谢功能的实现有直接关系。其次与各器官、系统的协调有关。 学生利用自制课件讲解,体验成就感,锻炼能力,创造一种生生交流、师生交流的氛围。学生倾听。 机体内各个器官、系统,为什么能保持协调一致?简要介绍人类对机体维持稳态机制的认识过程,指出目前普遍认为,神经—体液—免疫调节网络是机体维持稳态的主要调节机制。机体对稳态进行调节的能力是有限的,当外界环境变化过于剧烈,或人体自身的调节功能出现障碍,内环境稳态就会遭到破坏。内环境稳态遭破坏后会出现什么现象呢? 学生举例,如尿毒症、糖尿病、高山缺氧反应、发高烧、严重腹泻造成的脱水、酸碱中毒等。 请同学列举几个稳态失调的病例,说明症状和危害。在同学充分列举的基础上,教师给予适度的补充和修正。为什么内环境稳态失调后,会对机体造成危害?引导学生从细胞代谢需要的物质和条件进行分析,最后总结出:内环境稳态是机体进行正常生命活动的必要条件。 启发学生思考,与生活经验建立联系。学生讨论。 如何预防内环境稳态失调、保持机体健康?引导学生从外界环境和机体自身调节能力两个方面去思考。即通过加强自我保健,减少外界环境变化对机体的不良影响,同时增强机体的调节能力以适应多变的外环境。具体如何做?学生讨论,总结。1.保护我们的生存环境,防治环境污染。2.加强自我保健,为机体保持健康创造有利条件。尤其是处于比较恶劣的工作环境中的人,更应注意自身保健,如边防战士注意保暖、炼钢工人注意降温、抗洪战士注意补充水盐等。了解这些知识后才能懂得如何关爱自身和他人。3.加强体育锻炼,增强体质,提高机体适应外界环境的能力。 通过讨论,促进学生关注健康问题,强化自我保健和关爱他人的意识和能力。四、其他问题及其对策关于“体温日变化规律”的调查。(1)在此项调查中需要家长的协作配合。家长工作繁忙,教师有必要提前给家长发一封信,恳请家长配合学校的教学工作,协助孩子完成这项调查活动。(2)选择好布置活动的时间。由于这项活动需要测量一日内7个时刻的体温,应选择父母和孩子共同的休息日来完成。(3)布置作业时应就体温的知识和测量体温的方法进行培训。可参考下面的内容:人的体温是指人身体内部的温度,即内环境的温度。由于身体内部的温度不容易测量,所以临床上常以口腔、腋窝和直肠的温度来代表体温。在本次调查活动中我们用腋窝温度代表体温。(4)布置作业时要明确以下要求,即在进行这项活动时,不仅要完成体温的测量,还要完成思考题的回答,为下节课的讨论做好准备。二、探究指导──实验“生物体维持ph稳定的机制”(一)实验的准备(1)实验试剂的配制方法①0.1 mol/l naoh:将4 g naoh放在1 l的烧杯内,缓缓加入500 ml蒸馏水,不停地搅拌直至溶解。然后定容至1 000 ml。②0.1 mol/l hcl:将8 ml浓盐酸加于500 ml蒸馏水中,再定容至1 000 ml。③ph=7的磷酸缓冲溶液:先配制0.1 mol/l na2hpo4和0.1 mol/l nah2po4两种溶液。具体配制方法如下:将26.8 g na2hpo4•7h2o在容量瓶中溶解再定容至1 000 ml;将13.8 g nah2po4•h2o在容量瓶内溶解再定容至1 000 ml。然后将这两种溶液混合,可通过调整两种溶液的比例将混合液调至所需的ph。④肝匀浆:将10 g新鲜的或冷冻的肝放入100 ml蒸馏水中,用匀浆机或研钵捣碎(肝的用量会影响匀浆的缓冲能力)。⑤马铃薯匀浆:将10 g马铃薯块茎放入100 ml蒸馏水中,用匀浆机或研钵捣碎(材料的用量会影响匀浆的缓冲能力)。⑥黄瓜匀浆:配制方法同上。⑦鸡蛋清:用水5∶1稀释鸡蛋清,搅拌均匀。(2)4人一组,每组至少测4种溶液的变化:自来水、缓冲液和2种生物材料(由教师指定,一种是植物材料、一种是动物材料),提前完成的小组可多测几种生物材料。肝匀浆、马铃薯匀浆都是较理想的实验材料,也可选用下表中的常见材料。生物材料 ph 生物材料 ph 生物材料 ph苹果 2.9~3.3 牛奶 6.4~6.8 虾 5.8~7.0扁豆 5.0~6.0 柑橘 3.0~4.0 番茄 4.1~4.4人血浆 7.3~7.5 豌豆 5.8~6.4 人尿 4.8~8.4白面包 5.0~6.0 酸菜 2.2~3.5 柠檬 2.2~2.5胡萝卜 4.9~5.2 人唾液 6.0~7.6 人乳汁 6.6~7.6玉米 5.0~6.5 鲑鱼肉 6.1~6.3 葡萄酒 2.8~3.8(二)实验教学的策略1.加强预习环节,培养主动学习的习惯。本实验指导具体明确,适合学生自学。加强预习环节有利于敦促学生转变学习观念,养成主动学习的习惯。同时,按照课时安排,本实验要求用1课时完成,既要完成操作又要完成讨论,时间很紧张。学生若能在课前进行充分预习,就能够节约课堂时间,提高教学效率。不同学生预习效果不同,为保证实验质量,教师仍有必要在学生预习的基础上,通过提问的方式使学生明确本实验的目的、操作的要点及其他注意事项。2.重视组织教学,提高实验课效率。本实验的组织形式以小组活动为主,教师应对小组活动给予指导。进行实验操作时,小组成员应进行合理分工,以确保在规定的时间内完成实验。绘制ph变化曲线图适宜以个人为单位进行,这样能使每个同学都得到锻炼的机会。进行讨论时,应以小组为单位,以利于相互启发、集思广益。实验结束后的总结,则应当面向全体学生。3.加强讨论和总结,落实教学目标。由于时间紧张,实验课草草收场是常有的事情。这样做的结果是,课上做得热热闹闹,课下忘得干干净净,不利于全面提高学生的实验能力和落实教学目标。因此,教师在课前要精心安排好实验课的各个环节,在课堂上要有效地进行调控,保证最后有足够的时间进行讨论和总结。为便于开展实验后的讨论,应倡导学生带着问题做实验,在动手操作的同时,积极动脑思考,这样才能使讨论深入而有效。本实验中的讨论题2和3涉及缓冲作用的机理,需要利用化学知识才能解释清楚,教师在课前应查阅相关的化学教材或请教化学老师,既给自己补充相关知识,也可了解学生的化学基础。五、答案和提示(一)问题探讨1.提示:血浆生化指标指的是血浆中各种化学成分的含量,其中包括机体多种代谢产物的含量。健康机体的生化指标一般都处于正常范围内。当机体某项生理功能出现障碍时,势必影响其代谢产物的含量,因此血浆的生化指标可以反映机体的健康状况,并可以作为诊断疾病的依据。例如,正常情况下,转氨酶主要分布在各种组织的细胞内,以心脏和肝脏的活性,在血浆中的活性很低。当某种原因使细胞膜通透性增高时,或因组织坏死细胞破裂后,可有大量转氨酶进入血浆,引起血浆中转氨酶活性升高。2.提示:这说明(1)内环境中各种化学成分的含量不是恒定不变的,而是在一定范围内波动,内环境的稳定是一种动态的相对稳定;(2)不同个体存在一定差异。3.提示:(1)肌酐含量超标,肌酐是有毒的代谢废物,积累过多会影响健康。这表明肾脏的排泄功能有障碍。(2)葡萄糖含量超标,血糖含量过高可并发酮症酸中毒、糖尿病的心血管合并症等。(3)甘油三脂超标,可引起高脂血症,易并发冠心病、动脉粥样硬化等。练习:p11 一、基础题 p13 一、概念检测

4、高一英语人教版必修三全册课文内容

unit 1 festivals around the world festivals and celebrations festivals and celebrations of all kinds have been held everywhere since ancient times. most ancient festivals would celebrate the end of cold weather, planting in spring and harvest in autumn. sometimes celebrations would be held after hunters had caught animals. at that time people would starve if food was difficult to find, especially during the cold winter months. today’s festivals have many origins, some religious, some seasonal, and some for special people or events. festivals of the dead some festivals are held to honour the dead or to satisfy the ancestors, who might return either to help or to do harm. for the japanese festival obon, people should go to clean graves and light incense in memory of their ancestors. they also light lamps and play music because they think that will lead the ancestors back to earth. in mexico, people celebrate the day of the dead in early november. on this important feast day, people eat food in the shape of skulls and cakes with “bones” on them. they offer food, flowers and gifts to the dead. the western holiday halloween also had its origin in old beliefs about the return of the spirits of dead people. it is now a children’s festival, when they can dress up and go to their neighbours’ homes to ask for sweets. if the neighbours do not give any sweets, the children might play a trick on them. festivals to honour people festivals can also be held to honour famous people. the dragon boat festival in china honours the famous ancient poet, qu yuan. in the usa, columbus day is in memory of the arrival of christopher columbus in the new world. india has a national festival on october 2 to honour mohandas gandhi, the leader who helped gain india’s independence from britain. harvest festivals harvest and thanksgiving festivals can be very happy events. people are grateful because their food is gathered for the winter and the agricultural work is over. in european countries, people will usually decorate churches and town halls with flowers and fruit, and will get together to have meals. some people might win awards for their farm produce, like the biggest watermelon or the most handsome rooster. china and japan have mid-autumn festivals when people admire the moon and in china enjoy moon-cakes. spring festivals the most energetic and important festivals are the ones that look forward to the end of winter and to the coming of spring. at the spring festival in china, people eat dumplings, fish and meat and may give children lucky money in red paper. there are dragon dances and carnivals, and families celebrate the lunar new year together. some western countries have very exciting carnivals, which take place forty days before easter, usually in february. these carnivals might include parades, dancing in the streets day and night, loud music and colourful clothing of al kinds. easter is an important religious and social festival for christians around the world. it celebrates the return of jesus from the dead and the coming of spring and new life. japan’s cherry blossom festival happens a little later. the country, covered with cherry tree flowers, looks as though it is covered with pink snow. people love to get together to eat, drink and have fun with each other. festivals let us enjoy life, be proud of our customs and forget our work for a little while.a sad love story li fang was heart-broken. it was valentine’s day and hu jin had said she would meet him at the coffee shop after work. but she didn’t turn up. she could be with her friends right now laughing at him. she said she would be there at seven o’clock, and he thought she would keep her word. he had looked forward to meeting her all day, and now he was alone with his roses and chocolates, like a fool. well, he was not going to hold his breath for her to apologize. he would drown his sadness in coffee. it was obvious that the manager of the coffee shop was waiting for li fang to leave - he wiped the tables, then sat down and turned on the tv - just what li fang needed! a sad chinese story about lost love. the granddaughter of the goddess of heaven visited the earth. her name was zhinü, the weaving girl. while she was on earth she met the herd boy niulang and they fell in love. (“just like me and hu jin,” thought li fang.) they got married secretly, and they were very happy. (“we could be like that,” thought li fang.) when the goddess of heaven knew that her granddaughter was married to a human, she became very angry and made the weaving girl return to heaven. niu lang tried to follow her, but the river of stars, the milky way, stopped him. finding that zhinü was heart-broken, her grandmother finally decided to let the couple cross the milky way to meet once a year. magpies make a bridge of their wings so the couple can cross the river to meet on the seventh day of the seventh lunar month. people in china hope that the weather will be fine on that day, because if it is raining, it means that zhinü is weeping and the couple won’t be able to meet. the announcer said, “this is the story of qiqiao festival. when foreigners hear about the story, they call it a chinese valentine’s story. it’s a fine day today, so i hope you can call all meet the one you love.” as li fang set off for home, he thought, “i guess hu jin doesn’t love me. i’ll just throw these flowers and chocolates away. i don’t want them to remind me of her.” so he did. as he sadly passed the tea shop on the corner on his way home, he heard a voice calling him. there was hu jin waving at him and calling, “why are you so late? i’ve been waiting for you for a long time! and i have a gift for you!” what would he do? he had thrown away her valentine gifts! she would never forgive him. this would not be a happy valentine’s day! unit 2 healthy eating come and eat here (i) wang peng sat in his empty restaurant feeling very frustrated. it had been a very strange morning. usually he got up early and prepared his menu of barbecued mutton kebabs, roast pork, stir-fried vegetables and fried rice. then by lunchtime they would all be sold. by now his restaurant ought to be full of people. but not today! why was that? what could have happened? he thought of his mutton, beef and bacon cooked in the hottest, finest oil. his cola was sugary and cold, and his ice cream was made of milk, cream and delicious fruit. “nothing could be better,” he thought. suddenly he saw his friend li chang hurrying by. “hello, lao li,” he called. “your usual?” but li chang seemed not to hear. what was the matter? something terrible must have happened if li chang was not coming to eat in his restaurant as he always did. wang peng followed li chang into a new small restaurant. he saw a sign at the door. tired of all that fat? want to lose weight? come inside yong hui’s slimming restaurant. only slimming foods served here.make yourself thin again! curiosity drove wang peng inside. it was full of people. the hostess, a very thin lady, came forward. “welcome,” she said. “my name is yong hui. i’ll help you lose weight and be fit in two weeks if you eat here every day.” then she gave a menu to wang peng. there were few choices of food and drink on it: just rice, raw vegetables served in vinegar, fruit and water. wang peng was amazed at this and especially at the prices. it cost more than a good meal in his restaurant! he could not believe his eyes. he threw down the menu and hurried outside. on his way home he thought about his own menu. did it make people fat? perhaps he should go to the library and find out. he could not have yong hui getting away with telling people lies! he had better do some research! at the library wang peng was surprised to find that his restaurant served far too much fat and yong hui’s far too little. even though her customers might get thin after eating yong hui’s food, they were not eating enough energy-giving food to keep them fit. they would become tired very quickly. wang peng felt more hopeful as he drove back home. perhaps with a discount and a new sign he could win his customers back. so he wrote: want to feel fit and energetic? come and eat here! discounts today! our food gives you energy all day! the competition between the two restaurants was on! come and eat here (ii) a week later, wang peng’s restaurant was nearly full and he felt happier. perhaps he would be able to earn his living after all and not have to close his restaurant. he did not look forward to being in debt because his restaurant was no longer popular. he smiled as he welcomed some customers warmly at the door but the smile left his face when he saw yong hui walking in. she did not look happy but glared at him. “may i ask what you were doing in my restaurant the other day? i thought you were a new customer and now i know that you only came to spy on me and my menu,” she shouted. “please excuse me,” he calmly explained, “i wanted to know where all my customers had gone last week. i followed one of them and found them in your restaurant. i don’t want to upset you, but i found your menu so limited that i stopped worrying and started advertising the benefits of my food. why don’t you sit down and try a meal?” yong hui agreed to stay and soon they were both enjoying dumplings and breast of chicken cooked with garlic. when they were served the ice cream, yong hui began to look ill. “i feel sick with all this fat and heavy food,” she said, “i miss my vegetables and fruit.” wang peng was enjoying a second plate of dumplings so he sighed. “yes,” he added, “and i would miss my dumplings and fatty pork. don’t you get tired quickly?” “well, i do have to rest a lot,” admitted yong hui. “but don’t you think it would be better if you were a bit thinner? i’m sure you’d feel much healthier.” they began to talk about menus and balanced diets. “according to my research, neither your restaurant nor mine offers a balanced diet,” explained wang peng. “i don’t offer enough fibre and you don’t offer enough body-building and energy-giving food. perhaps we ought to combine our ideas and provide a balanced menu with food full of energy and fibre.” so that is what they did. they served raw vegetables with the hamburgers and boiled the potatoes rather than fried them. they served fresh fruit with the ice cream. in this way they cut down the fat and increased thefibre in the meal. their balanced diets became such a success that before long wang peng became slimmer and yong hui put on more weight. after some time the two found that their business cooperation had turned into a personal one. finally they got married and live happily ever after. unit 3 the million pound bank note the million pound bank note act i, scene 3 narrator: it is the summer of 1903. two old and wealthy brothers, roderick and oliver, have made a bet. oliver believes that with a million pound bank note a man could survive a month in london. his brother roderick doubts it. at this moment, they see a penniless young man wandering on the pavement outside their house. it is henry adams, an american businessman, who is lost in london and does not know what he should do. roderick: young man, would you step inside a moment, please? henry: who? me, sir? roderick: yes, you. oliver: through the front door on your left. henry: (a servant opens a door) thanks. servant: good morning, sir. would you please come in? permit me to lead the way, sir. oliver: (henry enters) thank you, james. that will be all. roderick: how do you do, mr … er …? henry: adams. henry adams. oliver: come and sit down, mr adams. henry: thank you. roderick: your are an american? henry: that’s right, from san francisco. roderick: how well do you know london? henry: not at all. it’s my first trip here. roderick: i wonder, mr adams, if you mind us asking a few questions? henry: not at all. go right ahead. roderick: may we ask what you’re doing in this country and what your plans are? henry: well, i can’t say that i have any plans. i’m hoping to find work. as a matter of fact, i landed in britain by accident. roderick: how is that possible? henry: well, you see, back home i have my own boat. about a month ago, i was sailing out of the bay … (his eyes stare at what is left of the brothers’ dinner on the table) oliver: well, go on. henry: oh, yes. well, towards nightfall i found myself carried out to sea by a strong wind. it was all my fault. i didn’t know whether i could survive until morning. the next morning i’d just about given myself up for lost when i was spotted by a ship. oliver: and it was the ship that brought you to england. henry: yes. the fact is that i earned my passage by working as an unpaid hand, whichaccounts for my appearance. i went to the american embassy to seek help, but … (the brothers smile at each other) roderick: well, you mustn’t worry about that. it’s an advantage. henry: i’m afraid i don’t quite follow you, sir. roderick: tell us, mr adams, what sort of work did you do in america? henry: i worked for a mining company. could you offer me some kind of work here? roderick: patience, mr adams. if you don’t mind, may i ask how much money you have? henry: well, to be honest, i have none. roderick: (happily) what luck! brother, what luck! (claps his hands together) henry: well, it may seem lucky to you but not to me! on the contrary, in fact. if this is your idea of some kind of joke, i don’t think it’s very funny. (henry stands up to leave) now if you’ll excuse me, i think i’ll be on my way. roderick: please don’t go mr adams. you mustn’t think we don’t care about you. oliver, give him the letter. oliver: yes, the letter. (gets it from a desk and gives it to henry like a gift) the letter. henry: (taking it carefully) for me? roderick: for you. (henry starts to open it) oh, no, you mustn’t open it. not yet. you can’t open it until two o’clock. henry: oh, this is silly. roderick: not silly. there’s money in it. (calls to the servant) james? henry: oh, no. i don’t want your charity. i just want an honest job. roderick: we know you’re hard-working. that’s why we have given you the letter. james, show mr adams out. oliver: good luck, mr adams. henry: well, why don’t you explain what this is all about? roderick: you’ll soon know. (looks at the clock) in exactly an hour and a half. servant: this way, sir. roderick: mr adams, not until 2 o’clock. promise? henry: promise. goodbye. unit 4 astronomy: the science of the stars how life began on the earth no one knows exactly how the earth began, as it happened so long ago. however, according to a widely accepted theory, the universe began with a “big bang” that threw matter in all directions. after that, atoms began to form and combine to create stars and other bodies. for several billion years after the “big bang”, the earth was still just a cloud of dust. what it was to become was uncertain until between 4.5 and 3.8 billion years ago when the dust settled into a solid globe. the earth became so violent that it was not clear whether the shape would last or not. it exploded loudly with fire and rock. they were in time to produce carbon dioxide, nitrogen, water vapour and other gases, which were to make the earth’s atmosphere. what is even more important is that as the earth cooled down, water began to appear on its surface. 第5 / 9页 water had also appeared on other planets like mars but, unlike the earth, it had disappeared later. it was not immediately obvious that water was to be fundamental to the development of life. what many scientists believe is that the continued presence of water allowed the earth to dissolve harmful gases and acids into the oceans and seas. this produced a chain reaction, which made it possible for life to develop. many millions of years later, the first extremely small plants began to appear on the surface of the water. they multiplied and filled the oceans and seas with oxygen, which encouraged the later development of early shellfish and all sorts of fish. next, green plants began to grow on land. they were followed in time by land animals. some were insects. others, called amphibians, were able to live on land as well as in the water. later when the plants grew into forests, reptiles appeared for the first time. they produced young generally by laying eggs. after that, some huge animals, called dinosaurs, developed. they laid eggs too and existed on the earth for more than 140 million years. however, 65 million years ago the age of the dinosaurs ended. why they suddenly disappeared still remains a mystery. this disappearance made possible the rise of mammals on the earth. these animals were different from all life forms in the past, because they gave birth to young baby animals and produced milk to feed them. finally about 2.6 million years ago some small clever animals, now with hands and feet, appeared and spread all over the earth. thus they have, in their turn, become the most important animals on the planet. but they are not looking after the earth very well. they are putting too much carbon dioxide into the atmosphere, which prevents heat from escaping from the earth into space. as a result of this, many scientists believe the earth may become too hot to live on. so whether life will continue on the earth for millions of years to come will depend on whether this problem can be solved. a visit to the moon last month i was lucky enough to have a chance to make a trip into space with my friend li yanping, an astronomer. we visited the moon in our spaceship! before we left, li yanping explained to me that the force of gravity would change three times on our journey and that the first change would be the most powerful. then we were off. as the rocket rose into the air, we were pushed back into our seats because we were trying to escape the pull of the earth’s gravity. it was so hard that we could not say anything to each other. gradually the weight lessened and i was able to talk to him. “why is the spaceship not falling back to the earth? on the earth if i fall from a tree i will fall to the ground.” i asked. “we are too far from the earth now to feel its pull,” he explained, “so we feel as if no gravity at all. when we get closer to the moon, we shall feel its gravity pulling us, but it will not be as strong a pull as the earth’s.” i cheered up immediately and floated weightlessly around in our spaceship cabin watching the earth become smaller and the moon larger. when we got there, i wanted to explore immediately. “come on,” i said. “if you are right, my weight will be less than on the earth because the moon is smaller and i will be able to move more freely. i might even grow taller if i stay here long enough. i shall certainly weigh less!” i laughed and climbed down the steps from the spaceship. but when i tried to step forward. i found i was carried twice as far as on the earth and fell over. “oh dear,” i cried, “walking does need a bit of practice now that gravity has changed.” after a while i got the hang of it and we began to enjoy ourselves. 第6 / 9页 leaving the moon’s gravity was not as painful as leaving the earth’s. but returning to the earth was very frightening. we watched, amazed as fire broke out on the outside of the spaceship as the earth’s gravity increased. again we were pushed hard into our seats as we came back to land. “that was very exhausting but very exciting too,” i said. “now i know much more about gravity! do you think we could visit some stars next time?” “of course,” he smiled, “which star would you like to go to?” unit 5 canada- “the true north”

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