1、大学英语四级模拟试卷 893及答案与解析 一、 Part I Writing (30 minutes) 1 For this part. you are allowed thirty minutes to write An Application Letter. You should write at least 120 following the outline given below in Chinese: An Application Letter 1.对该学校很感兴趣。想报考该校的 MBA研 究生。 2.介绍自己在北京的学业情况。 3.表达自己求学的迫切心情。 二、 Part II R
2、eading Comprehension (Skimming and Scanning) (15 minutes) Directions: In this part, you 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
3、 NO) if the statement contradicts the information given in the passage; NG (for NOT GIVEN) if the information is not given in the passage. 1 THE HYDROGEN ECONOMY It seems-like every day there is a new announcement in the news about automobiles powered by fuel cells. The promises are great, since fue
4、l cells have the potential to very quickly double the efficiency of cars while significantly reducing air pollution. At the same time, there have been news stories for decades about the problems associated With petroleum. Everything from oil spills to ozone(臭氧 ) alerts to global warming gets blamed
5、on our dependence on fossil(化石 ) fuels. These two forces are leading the world toward what is broadly known as the hydrogen economy. If the predictions are true, over the next several decades we will all begin to see an amazing shift away from the fossil fuel economy we have today toward a much clea
6、ner hydrogen future. Problems with the fossil fuel economy While fossil fuels have played an important role in getting society to the point it is at today, there are four big problems that fossil fuels create: Air pollution-When cars burn gasoline, the internal combustion engine also produces: Carbo
7、n monoxide, a poisonous gas Nitrogen oxides, the main source of urban smog Unburned hydrocarbons, the main source of urban ozone Environmental pollution-The process of transporting and storing oil has a big impact on the environment whenever something goes wrong. An oil spill, pipeline explosion or
8、well fire can create a huge mess. Global warming The carbon dioxide coming out of every cars tailpipe is a greenhouse gas that is slowly raising the temperature of the planet. The ultimate effects are unknown, but it is a strong possibility that, eventually, there will be dramatic climate changes th
9、at affect everyone on the planet. Dependence-The United States, and most other Countries, cannot produce enough oil to meet demand, so they import it from oil-rich countries. That creates an economic dependence. When Middle East oil producers decide to raise the price of oil, the rest of the world h
10、as little choice but to pay the higher price. Advantages of the hydrogen economy The hydrogen economy promises to eliminate all of the problems that the fossil fuel economy creates. Therefore, the advantages of the hydrogen economy include: The elimination of pollution caused by fossil fuels-When hy
11、drogen is used in a fuel cell to create power, it is a completely clean technology. The only byproduct is water. There are also no environmental dangers like oil spills to worry about with hydrogen. The elimination of greenhouse gases-If the hydrogen comes from the electrolysis of water, then hydrog
12、en adds no greenhouse gases to the environment. There is a perfect cycle-electrolysis produces hydrogen from water, and the hydrogen recombines with oxygen to create water and power in a fuel cell. The elimination of economic dependence-The elimination of oil means no dependence on the Middle East a
13、nd its oil reserves. Distributed production-Hydrogen can be produced anywhere that you have electricity and water. People can even produce it in their homes with relatively simple technology. The problems with the fossil fuel economy are so great, and the environmental advantages of the hydrogen eco
14、nomy so significant, that the push toward the hydrogen economy is very strong. Technological Hurdles(障碍 ) The big question with the hydrogen economy is, “Where does the hydrogen come from?“ After that comes the question of transporting, distributing and storing hydrogen. Hydrogen tends to be large a
15、nd tricky in its natural gaseous form. Once both of these questions are answered in an economical way, the hydrogen economy will be in place. Where does the hydrogen come from? There are two possible sources for the hydrogen: Electrolysis of water-Using electricity, it is easy to split water molecul
16、es to create pure hydrogen and oxygen. One big advantage of this process is that you can do it anywhere. For example, you could have a box in your garage producing hydrogen from tap water, and you could fuel your car with that hydrogen. Reforming fossil fuels-Oil and natural, gas contain hydrocarbon
17、s-molecules consisting of hydrogen and carbon. Using a device called a fuel processor or a reformer, you can split the hydrogen off the carbon in a hydrocarbon relatively easily and then use the hydrogen. You discard the leftover carbon to the atmosphere as carbon dioxide. The second option is, of c
18、ourse, slightly perverse(不正当的 ). You are using fossil fuel as the source of hydrogen for the hydrogen economy. This approach reduces air pollution, but it doesnt solve either the greenhouse gas problem or the dependence problem. However, it may be a good temporary step to take during the transition(
19、转变 ) to the hydrogen economy. The interesting thing about the first option is that it is the core of the real hydrogen economy. To have a pure hydrogen economy, the hydrogen must be derived from renewable sources rather than fossil fuels so that we stop releasing carbon into the atmosphere. Having e
20、nough electricity to separate hydrogen from water, and generating that electricity without using fossil fuels, will be the biggest change that we see in creating the hydrogen economy. Where will the electricity for the electrolysis of water come from? Currently, about 68 percent of the electricity p
21、roduced in the United States comes from coal or natural gas. All of that generating capacity will have to he replaced by renewable sources in the hydrogen economy. Right now there are several different ways to create electricity that do not use fossil fuels: Nuclear power Hydroelectric dams Solar ce
22、lls Wind turbines Geothermal power Wave and tidal power Co-generation How do you store and transport the hydrogen? Hydrogen is a large gas of its kind, and it is not nearly as easy to work with as gasoline. Compressing the gas requires energy, and compressed hydrogen contains far less energy than th
23、e same volume of gasoline. However, solutions to the hydrogen storage problem are surfacing. For example, hydrogen can be stored in a solid form in a chemical called sodium borohydride. Once the storage problem is solved and standardized, then a network of hydrogen stations and the transportation in
24、frastructure will have to develop around it. The main barrier to this might be the technological sorting-out process. Stations will not develop quickly until there is a storage technology that clearly dominates the marketplace. For instance, if all hydrogen-powered cars from all manufacturers used s
25、odium borohydride, then a station network could develop quickly; that sort of standardization is unlikely to happen rapidly, if history is any guide. Prospects for the future You will hear more and more about the hydrogen economy in the news in the Coming months, because the drumbeat is growing loud
26、er. The environmental problems of the fossil fuel economy are combining with breakthroughs(突破 ) in fuel-cell technology, and the pairing will allow us to take the first steps, The most obvious step we will see is the marketing of fuel-cell-powered vehicles. Although they will be powered initially by
27、 gasoline and reformers, fuel cells represent two major improvements over the internal combustion engine: They are about twice as efficient. They can significantly reduce air pollution in cities. 2 The passage gives a general description of the benefits and potential problems of a hydrogen economy.
28、（ A） Y （ B） N （ C） NG 3 An oil spill can pose a big problem to the environment. （ A） Y （ B） N （ C） NG 4 Compared with other major industrialized countries, the United States depends more heavily on oil import. （ A） Y （ B） N （ C） NG 5 Even if you have electricity and water, you still cannot produce h
29、ydrogen everywhere. （ A） Y （ B） N （ C） NG 6 In the United States, most of the electricity is generated from coal or natural gas. （ A） Y （ B） N （ C） NG 7 We must derive hydrogen from renewable sources with a view to a pure hydrogen economy. （ A） Y （ B） N （ C） NG 8 So far, there seems to be no solutio
30、n in sight as to how the hydrogen can be stored. （ A） Y （ B） N （ C） NG 9 Possible sources for the hydrogen are both electrolysis of water and _. 10 If the storage problem is _ and _, a network of hydrogen stations and the transportation infrastructure will have to develop around it. 11 Concerning th
31、e future of the hydrogen economy, the most obvious step we will take is _. 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 ques
32、tions will be spoken only once. After each question there 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） It is about to start raining. （ B） The rain will stop soon. （ C） It has been raining all day. （ D） It just stopp
33、ed raining. （ A） Cell phones are more convenient when they are smaller. （ B） He should change his thinking and understand that smaller phones are better. （ C） He should accept the fashion. （ D） Cell phones are not worth buying these days. （ A） Japanese. （ B） Arabic. （ C） Spanish. （ D） Chinese. （ A）
34、The food at the new restaurant is not very good. （ B） He has not been to the new restaurant yet. （ C） He would like to go to the new restaurant with the woman. （ D） A restaurants atmosphere is very important to him. （ A） She isnt sure about where things are on campus. （ B） The man should not ask the
35、 registration office. （ C） The registration is outside of the building. （ D） The people outside are very good to ask. （ A） The fault was the University. （ B） The man should have seen the light. （ C） The lights were net working that night. （ D） There were lights there since she has seen them. （ A） Je
36、nnifer is wearing a bandage over her leg. （ B） Jennifer will be a runner. （ C） Jennifers brother hit her in the leg. （ D） Jennifer tried to climb the tree. （ A） Lending something to a student. （ B） Reading a students application. （ C） Asking for some financial aid. （ D） Borrowing money for a busines
37、s. （ A） To invite him to a cookout. （ B） To ask if she can borrow his car. （ C） To tell him about a trip she took. （ D） To convince him to go on a canoe trip. （ A） Food. （ B） A sleeping bag. （ C） A canoe. （ D） A tent. （ A） Because she will tell him what time they are leaving. （ B） Because she will a
38、sk him whether his car is available. （ C） Because she will find out what kind of food he is bringing. （ D） Because she will find out whether he wants to go canoeing. （ A） Food packaging. （ B） A new fast food. （ C） Varieties of fish. （ D） An artificial flavor. （ A） Fast food. （ B） Tomato flavor. （ C）
39、 The taste of fish. （ D） The smell of cheese. （ A） Its low purchase price. （ B） Its nutritious value. （ C） Its wide availability. （ D） Its higher water content. （ A） In a few weeks. （ B） In about two years. （ C） In two or three months. （ D） In half a year. Section B Directions: In this section, you
40、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 only once. After you hear a question, you must choose the best answer from the four choices marked A, B, C and D. （ A） She was a tailor. （ B） She was an engineer. （
41、 C） She was an educator. （ D） She was a public speaker. （ A） Basing them on science-fiction movies. （ B） Including interesting examples in them. （ C） Adjusting them to different audiences. （ D） Focusing on the latest progress in space science. （ A） Whether spacemen carry weapons. （ B） How spacesuits
42、 protect spacemen. （ C） How NASA trains its spacemen. （ D） What spacemen eat and drink. （ A） Family violence. （ B） The Great Depression. （ C） Her fathers disloyalty. （ D） Her mothers bad temper. （ A） His advanced age. （ B） His childrens efforts. （ C） His improved financial condition. （ D） His second
43、 wifes positive influence. （ A） Love is blind. （ B） Love breeds love. （ C） Divorce often has disastrous consequences. （ D） Happiness is hard to find in blended families. （ A） Close to the city centre. （ B） In the suburb. （ C） Inside the city. （ D） Far away from the city. （ A） Saving money. （ B） Trav
44、eling by bus. （ C） Enjoying city life. （ D） Traveling on foot. （ A） Sunday newspaper. （ B） Television program. （ C） Information agency. （ D） All the newspapers. （ A） It is more convenient to live in the hotel if you stay in the U.S. （ B） It can save much money to live away from the city. （ C） You ca
45、n rent a place for some time if you want to save money. （ D） Most people go visiting houses or apartments on Sunday morning. 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
46、 the passage is read for the second time, you are required to fill in the blanks numbered from 36 to 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
47、heard or write down the 36 Planning is a very important activity in our lives. It can give pleasure, even【 B1】_ , or it can cause quite【 B2】 _ headaches. The more【 B3】 _ the task ahead, the more careful the planning required. Getting to school or to work on time is a task requiring little or no plan
48、ning. And it is almost a【 B4】 _ . A months touring holiday【 B5】 _ , or better still, getting married, is a different matter altogether. If the matter【 B6】 _ a church wedding, a【 B7】 _ , a honeymoon in Venice, and returning to a new home, this requires even more planning to make sure that it is【 B8】
49、_ . Planning is our way of trying to ensure success and of avoiding costly failures we can not afford.【 B9】 _ the scale may vary, but the degree of importance does not. In essence,【 B10】 _ . Both are designed to ensure an adequate supply of essentials, and if properly carded out,【 B11】 _ . 37 【 B1】 38 【 B2】 39 【 B3】 40 【 B4】 41 【 B5】 42 【 B6】 43 【 B7】 44 【 B8】 45 【 B9】 46 【 B10】 47 【 B11】 Section A Directions: In this section, there
