1、Unit 4 Section IWarming Up & Reading.阅读理解AEdmund Halley was an English scientist who lived over 200 years ago. He studied the observations of comets (彗星) which other scientists had made. The orbit of one particular comet was a very difficult mathematical (数学) problem. He could not figure it out. Nei
2、ther could other scientists who dealt with such problems.However, Halley had a friend named Newton, who was a brilliant mathematician. Newton though he had already worked out that problem, but he could not find the papers on which he had done it. He told Halley that the orbit of a comet had the shap
3、e of an ellipse (椭圆)Now Halley set to work. He figured out (解决，计算出) the orbits of some of the comets that had been observed by scientists. He made a surprising discovery. The comets that had appeared in the years 1531, 1607, and 1682 all had the same orbit. Yet their appearances had been 75 to 76 ye
4、ars apart.This seemed very strange to Halley. The different comets followed the same orbit. The more Halley thought about it, the more he thought that there had not been three different comets, as people thought. He decided that they had simply seen the same comet three times. The comet had gone awa
5、y and had come back again.It was an astonishing idea! Halley felt certain enough to make a prediction (预言) of what comet would happen in the future. He decided that this comet would appear in the year 1758. There were 53 years to go before Halleys prediction could be tested. In 1758 the comet appear
6、ed in the sky. Halley did not see it, for he has died some years before. Ever since then that comet has been called Halleys comet, in his honor.【语篇解读】本文主要介绍了200多年前英国科学家哈雷以及他的发现。1Halley made his discovery .Aby doing experimentsBby means of his own careful observationCby using the work of other scient
7、istsDby chance解析：选C细节理解题。由文中第三段中的“He figured out (解决，计算出) the orbits of some of the comets that had been observed by scientists.”可知应选C。2Halley made a surprising, but correct prediction in the year .A1704 B1705C1706 D1707解析：选B数字计算题。第五段中的“He decided that this comet would appear in the year 1758. There
8、 were 53 years to go before Halleys prediction could be tested.”这句话告诉我们：他预言彗星出现的时间是1758年，而这个预言还要经过53年才能验证，由此可以推断出哈雷做出这个预言的时间是1705年。3This passage in general is about .AHalley and other scientistsBthe orbit of a cometCNewton and HalleyDHalley and his discovery解析：选D主旨大意题。文章的中心就是哈雷以及他的发现。4Which of the f
9、ollowing is TRUE?AEdmund Halley was an American scientist.BHalley made his discovery by doing experiments.CNewton was a famous mathematician.DThe orbit of a comet had the shape of a circle.解析：选C细节理解题。从文章首句可以看出A项错误；从第1题的分析中可知B项也错误；牛顿告诉哈雷彗星的轨道是椭圆形的，可排除D项。BSatellites are an important part of our ordina
10、ry lives. For example, the information for weather forecasts is sent by satellite. Some satellites have cameras which take photographs of the Earth to show how clouds are moving. Satellites are also used to connect our international phone calls.Computer connections of the World Wide Web and Internet
11、 also use satellites. Many of our TV programmes come to US through satellites. Airplane pilots also sometimes use a satellite to help them find their exact location.We use satellites to send television pictures from one part of the world to another. They are usually 35,880 kilometres above the equat
12、or (赤道). Sometimes we can see a satellite in the sky and it seems to stay in the same place. This is because it is moving around the world at 11,000 kilometres an hourexactly the same speed that the earth rotates (转动). A satellite must orbit the Earth with its antennae (天线) facing the earth. Sometim
13、es, it moves away from its orbit, so there are little rockets on it which are used to put the satellite back in the right position. This usually happens about every five or six days.Space is not empty! Every week, more and more satellites are sent into space to orbit the Earth. A satellite usually w
14、orks for about 1012 years. Satellites which are broken are sometimes repaired by astronauts or sometimes brought back to the Earth to be repaired. Often, very old or broken satellites are left in space to orbit the Earth for a very long time. This is very serious because some satellites use nuclear
15、power and they can crash into each other.【语篇解读】本文是一篇科普说明文。文章对各种卫星的用途、卫星工作的状态以及人们对已损坏卫星的处理办法进行了解释说明。5Which of the following is NOT done by satellites according to the passage?ASending information for weather forecasts.BTaking photographs of the Earth.CSending TV pictures.DProviding food for airplane
16、pilots.解析：选D细节理解题。根据第一段和第三段首句可以看出，卫星可以传递天气预报信息、拍摄地球照片、传递电视图片等，但是没说为飞行员提供食物，所以选择D项。6Why does the satellite move around the world at the same speed as the Earth rotates?AIn order to take photographs.BIn order to stay in a certain position in the orbit.CIn order to move away from its orbit.DIn order to
17、 send television pictures.解析：选B细节理解题。根据第三段内容可以看出，卫星之所以用和地球自转相同的速度绕地球旋转，是为了保持在一定位置上。显然B项正确。7What does the underlined word “This” in the 3rd paragraph refer to?AA satellite.BA little rocket.CA satellite seems to stay in the same place in the sky.DThe satellite puts the rockets in the right position.解析
18、：选C代词指代题。this在此替代前文的“Sometimes we can see a satellite in the sky and it seems to stay in the same place.”故选C项。8Which is true of satellites?AA satellite usually works for about 1012 years.BEvery time a satellite gets broken, it is brought back to the Earth to be repaired.CA broken satellite is never
19、left in space.DBroken satellites often crash into each other.解析：选A细节理解题。根据最后一段可以看出A项正确。.语法填空Friendship is one of the most important things in everyones life.1. is very difficult to find a better definition (定义) of friendship. A true friend is the person 2. can share all our sadness and double all ou
20、r happiness. He or she is always at our side to give us his or her help and comfort.Knowing how 3. (value) friendship is, we should be very careful with our choice of a friend. We should choose those people with a good character 4. our friends, but we must try to avoid 5. (make) friends with a bad m
21、an.Besides, we should forgive their mistakes and try to help them as much as possible.A true friend can always 6. (trust), loved and respected. If you tell a friend your secrets, he or she wont tell them to 7. . Friends share their joys and sorrows. They help each other when they are 8. trouble, and
22、 cheer each other up when they are sad.9. most important thing is that a friend always understands you. In conclusion,10. you have made a good friend, dont forget him or her.【语篇解读】作者在文中告诉我们如何选择朋友以及如何对待朋友。1解析：空处为形式主语，真正的主语是空格后的不定式短语，故空格处填代词It。答案：It2解析：先行词person指人，关系词在从句中作主语，故用who/that引导定语从句。答案：who/th
23、at3解析：空处在句中作表语，由此结合语境可知，形容词valuable符合题意。答案：valuable4解析：根据句意“我们应选择那些有优秀品质的人作为朋友”可知，空处填介词as。答案：as5解析：avoid后应该接动词ing形式作宾语。答案：making6解析：主语是动作的承受者，故空处应用被动语态。答案：be trusted7解析：根据句意可知，others符合题意。答案：others8解析：in trouble为介词短语，意为“处于困境中”。故填介词in。答案：in9解析：空后为形容词的最高级，故空格处填定冠词The。答案：The10解析：本句含有一个状语从句，结合句意“如果我们结交了一
24、位好朋友(当我们结交了一位好朋友的时候)”可知，应用if/when作状语从句的引导词。答案：if/when1observationn观察2orbit n轨道3make a surprising discovery 做出惊人的发现4weather forecast 天气预报5pilot n飞行员；导航员Some satellites have cameras which take photographs of the Earth to show how clouds are moving.分析关系代词which在句中引导定语从句，修饰先行词cameras；how在句中引导从句并作动词show的宾语。翻译有些卫星带有摄像机，它们对地球拍照来展示云层的运动。
