[外语类试卷]大学英语四级模拟试卷27及答案与解析.doc

1、大学英语四级模拟试卷 27 及答案与解析 一、 Part I Writing (30 minutes) 1 For this part, you are allowed to write a composition according to the data given bellow. You should write at least 120 words and you should base your composition on the outline. Population over 60 years old in the world Year 250 million 1980 360

2、 million 1990 440 million 1994 580 million 2007 In China: 132 million in total 1245(10.6%) 1. Write out the messages conveyed by the data. 2. Point out what measures China take and give your comments. 二、 Part II Reading Comprehension (Skimming and Scanning) (15 minutes) Directions: In this part, you

3、 will have 15 minutes to go over the passage quickly and answer the questions attached to the passage. For questions 1-7, mark： Y (for YES) if the statement agrees with the information given in the passage; N (for NO) if the statement contradicts the information given in the passage; NG (for NOT GIV

4、EN) if the information is not given in the passage. 2 The Greenhouse Effect Earths climate has been changing constantly over its 5-billion-year history. Sometimes, the climate has warmed so that the oceans have risen and covered much of the Earth. Each of the changes may seem extreme, but they usual

5、ly occurred slowly over many thousands of years. Ancient Climate History The first people arrived in America between 15,000 and 30,000 years ago. During that time, much of North America was covered by great ice sheets. Some 14,000 years ago, the last ice sheet began to melt very quickly. By 7,000 ye

6、ars ago, the ice was gone. This end to the ice ages caused big changes on the Earth. The changes caused many kinds of plants and animals to die. For example, mastodonselephant-like animalsand other large mammals that preferred cold climates may not have been able to live in the warmer, drier conditi

7、ons. The Little Ice Age Starting in the 14th century, Europeans lived through what is known as the “Little Ice Age.“ The Little Ice Age lasted for several hundred years. During the Little Ice Age, the advance of glaciers along with hard winters and famines caused some people to starve and others to

8、leave their homes. Recent Climate History The Earth has warmed about 1F in the last 100 years. And the four warmest years of the 20th century all happened in the 1990s. Periods of increased heat from the sun may have helped make the Earth warmer. But many of the worlds leading climatologists think t

9、hat the greenhouse gases people produce are making the Earth warmer, too. Scientists think the sea has risen partly because of melting glaciers and sea ice. When some glaciers melt, they release water into the sea and make it higher than it was before. Scientists also think that warmer temperatures

10、in the sea make it rise even more. Heat makes water expand. When the ocean expands, it takes up more space. What Might Happen? Scientists are not fortune-tellers. They dont know exactly what will happen in the future. But they can use special computer programs to find out how the climate may change

11、in the years ahead. And the computer programs tell us that the Earth may continue to get warmer. Together, the melting glaciers, rising seas, and computer models provide some good clues. They tell us that the Earths temperature will probably continue to rise as long as we continue increasing the amo

12、unt of greenhouse gases in the atmosphere. Scientists have to think like detectives. They look for clues to help them understand how the world works. Then they investigate the clues to find evidencereal facts that can give them a better idea of what is going on. Here are some of the ways that scient

13、ists gather evidence about climate, both past and present: Weather Stations Weather stations help us find out the temperature on the surface of the Earth. Weather stations use special thermometers that tell us the temperature. They can be set up almost anywhere on land. Weather stations also can tel

14、l us how fast the wind is moving and how much rain falls on the ground during a storm. Weather Balloons Almost everyone likes balloonsincluding scientists! Weather balloons are released to float high up into the atmosphere. They carry special instruments that send all kinds of information about the

15、weather back to people on the ground. Ocean Buoys A buoy is an object that floats on water, and is often used to warn boats away from dangerous places in the ocean or on a river. But some buoys have special instruments on them. These buoys can tell us the temperature and other things about the condi

16、tions of the atmosphere. Weather Satellites Humans send satellites into space to travel around the Earth. The satellites send back information to scientists on the ground. Some of the information they give us is about the weather and the Earths temperature. Ice Cores Some scientists who want to find

17、 out more about climate study ice for clues. Not just any icethey are studying the ice from glaciers that have been around for a very long time. They cut pieces of ice and look for air bubbles that were trapped in the ice hundreds or even thousands of years ago. The air bubbles help them discover wh

18、at the climate used to be like on Earth. The evidence they uncover is creating a historical record of regional temperatures and greenhouse gas concentrations dating back 160,000 years. Sediment Analyses Sediment is the earth and rock that has built up in layers over time. Scientists are learning a g

19、reat deal about past climate from studying these layers. Sediment layering provides information about where glaciers have been in the past. Ocean sediments provide a map of how ocean currents have flowed in the past. And fossilized pollen found in sediment layers tells us about where different plant

20、s have grown in the past. Tree Rings You can tell how old a tree is by counting its rings because it grows a new ring every year. Tree rings also can tell us how much precipitation fell each year in the place where the tree lives. What Does All of This Mean? Weather stations, balloons, ocean buoys,

21、and satellites tell us the Earths temperature today. Ice cores, sediment layers, and tree rings tell us about what the Earths climate has been like in the past. With this evidence, scientists are learning how climate changes over time. What Are Scientists Still Unsure About? How do clouds respond to

22、 changes in temperature and precipitation? How do oceans transport heat? How do climate and intense weather events like hurricanes affect each other? As scientists try to answer these and other questions, they will discover many more clues about how the Earths climate system works. It may seem hard

23、to believe that people can actually change the Earths climate. But scientists think that the things people do that send greenhouse gases into the air are making our planet warmer. Once, all climate changes occurred naturally. However, during the Industrial Revolution, we began altering our climate a

24、nd environment through agricultural and industrial practices. The Industrial Revolution was a time when people began using machines to make life easier. It started more than 200 years ago and changed the way humans live. Before the Industrial Revolution, human activity released very few gases into t

25、he atmosphere, but now through population growth, fossil fuel burning, and deforestation, we are affecting the mixture of gases in the atmosphere. Since the Industrial Revolution, the need for energy to run machines has steadily increased. Some energy, like the energy you need to do your homework, c

26、omes from the food you eat. But other energy, like the energy that makes cars run and much of the energy used to light and heat our homes, comes from fuels like coal and oil-fossil fuels. Burning these fuels releases greenhouse gases. 2 The passage gives a general description of ancient climate hist

27、ory. （ A） Y （ B） N （ C） NG 3 The Little Ice Age lasted for several years. （ A） Y （ B） N （ C） NG 4 The Earths temperature usually rises half a degree every century. （ A） Y （ B） N （ C） NG 5 With the help of computer programs, scientists have predicted that the earth will continue to get warmer in the

28、future. （ A） Y （ B） N （ C） NG 6 Weather stations can not only tell us about wind speed, but also about rainfall. （ A） Y （ B） N （ C） NG 7 Both weather balloons and ocean buoys can collect information about the temperature. （ A） Y （ B） N （ C） NG 8 Ice Cores are only useful for giving us information ab

29、out the current weather conditions. （ A） Y （ B） N （ C） NG 9 Scientists can figure out where glaciers have been in the past through _. 10 Scientists believe that the things people do that send _ gases into the air are making our planet warmer. 11 The need for energy to run machines has steadily incre

30、ased since the _. Section A Directions: In this section, you will hear 8 short conversations and 2 long conversations. At the end of each conversation, one or more questions will be asked about what was said. Both the conversation and the questions will be spoken only once. After each question there

31、 will be a pause. During the pause, you must read the four choices marked A, B, C and D, and decide which is the best answer. （ A） He is a good friend of the speakers. （ B） He doesnt support the same team as the speakers. （ C） He is usually pessimistic. （ D） He is usually optimistic. （ A） The woman

32、is sending money abroad. （ B） The woman has been sent money from abroad. （ C） There is more than one counter for international money transfers. （ D） The woman is at the wrong counter. （ A） Applying for a job. （ B） Learning a foreign language. （ C） Taking a writing course. （ D） Joining a dating agenc

33、y. （ A） The woman wants to sell something. （ B） The newspaper doesnt care what people want to advertise. （ C） The ad will be published immediately. （ D） The newspaper workers will not change the spelling of any words in the ad. （ A） They both like curry. （ B） They like different foods, but at the sa

34、me restaurants. （ C） They think that Thai curries are better than Indian ones. （ D） The woman is more willing to experiment than the man. （ A） The flat in Baker Street has already been rented. （ B） The flat is in a very good location. （ C） The woman might not be able to rent the flat in Baker Street

35、. （ D） Finding a flat in Baker Street is very difficult. （ A） She doesnt like keeping in touch with old friends. （ B） It offers the best combination of speed and low cost. （ C） She believes that, in the modern world, it is essential. （ D） She thinks that people who do not have email will lose touch

36、with their old friends. （ A） He is using his computer for work purposes. （ B） He often plays games on his computer. （ C） His computer makes his life easier. （ D） His client cannot use a computer. （ A） Because she wants to keep fit. （ B） Because the sports centre only offers aerobics classes for wome

37、n. （ C） Because that was the only class she knew about. （ D） We are not told. （ A） The same as at the old one. （ B） Small group and individual ones. （ C） Small group ones only. （ D） Individual ones only. （ A） He only eats healthy food. （ B） He only eats junk food. （ C） He usually eats unhealthy food

38、. （ D） His favorite snack is carrot cake. （ A） A house. （ B） A car. （ C） A hotel. （ D） An art gallery. （ A） He has many pets. （ B） He has three children. （ C） He doesnt need a larger house. （ D） His wife is pregnant. （ A） House sales company. （ B） Motor sales company. （ C） Food sales company. （ D） T

39、ravel agency. （ A） She is a travel agent. （ B） She is a(real) estate agent. （ C） She sells cars. （ D） She sells hotels. Section B Directions: In this section, you will hear 3 short passages. At the end of each passage, you will hear some questions. Both the passage and the questions will be spoken o

40、nly once. After you hear a question, you must choose the best answer from the four choices marked A, B, C and D. （ A） It cost too much time. （ B） The walls were too hard to engrave. （ C） The drawings were too simple to recognize. （ D） It wasnt portable. （ A） On the walls of caves. （ B） On a heavy cl

41、ay tablet. （ C） On woods. （ D） On cloth. （ A） 5,000 years ago. （ B） 4,000 years ago. （ C） 50,000 years ago. （ D） 40,000 years ago. （ A） Its merchant fleet ruled the Mediterranean. （ B） The secrets of Syrias glassmaking were known by Venices craftsmen. （ C） Venices glassmaking industry was artistical

42、ly influenced by Islam. （ D） It had more than 8,000 craftsmen at one point. （ A） It made a lot of noise. （ B） It caused fires frequently. （ C） The fire from the furnaces polluted the air. （ D） The city authorities didnt want to develop the glassmaking industry. （ A） 4,000. （ B） 3,000. （ C） 9,000. （

43、D） 7,000. （ A） His parents. （ B） His friends. （ C） His grandparents. （ D） His aunt and uncle. （ A） Tuna. （ B） Trout. （ C） Cod. （ D） Salmon. （ A） He really missed him. （ B） He cried a lot. （ C） He didnt care. （ D） His grandfather didnt die. （ A） Under his bed. （ B） Next to his shoes. （ C） Under the t

44、able. （ D） In the closet. Section C Directions: In this section, you will hear a passage three times. When the passage is read for the first time, you should listen carefully for its general idea. When the passage is read for the second time, you are required to fill in the blanks numbered from 36 t

45、o 43 with the exact words you have just heard. For blanks numbered from 44 to 46 you are required to fill in the missing information. For these blanks, you can either use the exact words you have just heard or write down the 37 The most important part of being a normal weight isnt looking a certain

46、wayits feeling good and staying healthy. Having too much body fat can be 【 B1】 _ to the body in many ways. The good news is that its never too late to make changes in eating and 【 B2】 _ habits to control your weight, and those changes dont have to be as big as you might think. So if you or someone y

47、ou know is obese or 【 B3】 _, this article can give you information and tips for dealing with the problem by 【 B4】 _ a healthier lifestyle. Being obese and being overweight are not exactly the same thing. An obese person has a large amount of extra body fat, not just a few extra pounds. People who ar

48、e obese are very overweight and at risk for serious health problems. To 【 B5】 _ if someone is obese, doctors and other health care 【 B6】 _ often use a 【 B7】 _ called body mass index(BMI). First, a doctor measures a persons height and weight. Then the doctor uses these numbers to 【 B8】 _ another numb

49、er, the BMI. Once the doctor has calculated a childs or teens BMI, he or she will plot this number on a specific chart to see how it compares to other people of the same age and gender. A person with a BMI above the 95th percentile(meaning the BMI is greater than that of 95% of people of the same age and gender) is generally considered overweight. 【 B9】 _. Obesity is the term used for extreme ove