1、大学英语四级模拟试卷 752 及答案与解析 一、 Part I Writing (30 minutes) 1 For this part, you are allowed 30 minutes to write a composition on the topic Nationwide Shortage of Power Supply. You should write at least 150 words according to the outline given below in Chinese: 1. 专家预测，自 2006年下半年出现的全国范围内的电力短缺目前仍呈不断加剧态势 2.
2、分析全国范围内缺电现象的原因（可从发电设备过于陈旧、高耗能行业的过快发展等方面加以分析） 3. 试提供缺电问题解决方案 二、 Part II Reading 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) i
3、f 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 GIVEN) if the information is not given in the passage. 2 THE HYDROGEN ECONOMY It seems-like every day there is a new announcement in the news ab
4、out automobiles powered by fuel cells. The promises are great, since fuel 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. Everyt
5、hing from oil spills to ozone(臭氧 ) alerts to global warming gets blamed 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
6、shift away from the fossil fuel economy we have today toward a much cleaner 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
7、 cars burn gasoline, the internal combustion engine also produces: Carbon 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 environ
8、ment whenever something goes wrong. An oil spill, pipeline explosion or 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
9、 possibility that, eventually, there will be dramatic climate changes that 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
10、 oil producers decide to raise the price of oil, the rest of the world has 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 econ
11、omy include: The elimination of pollution caused by fossil fuels When hydrogen 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
12、 gases If the hydrogen comes from the electrolysis of water, then hydrogen 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 ceil. The elimination of economic de
13、pendence The elimination of oil means no dependence on the Middle East and 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 ec
14、onomy are so great, and the environmental advantages of the hydrogen economy 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 trans
15、porting, distributing and storing hydrogen. Hydrogen tends to be large and 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: El
16、ectrolysis of water Using electricity, it is easy to split water molecules 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 h
17、ydrogen. Reforming fossil fuels Oil and natural gas contain hydrocarbons 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
18、 carbon to the atmosphere as carbon dioxide. The second option is, of course, 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.
19、However, it may be a good temporary step to take during the transition(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 foss
20、il fuels so that we stop releasing carbon into the atmosphere. Having enough 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 electrolys
21、is of water come from? Currently, about 68 percent of the electricity produced in the United States comes from coal or natural gas. All of that genera ting capacity will have to be replaced by renewable sources in the hydrogen economy. Right now there are several different ways to create electricity
22、 that do not use fossil fuels: Nuclear power Hydroelectric dams Solar cells 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 r
23、equires energy, and compressed hydrogen contains far less energy than the 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 sta
24、ndardized, then a network of hydrogen stations and the transportation infrastructure 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.
25、For instance, if all hydrogen-powered cars from all manufacturers used sodium 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 econom
26、y in the news in the coming months, because the drumbeat is growing louder. 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 o
27、f fuel-cell-powered vehicles. Although they will be powered initially by 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 de
28、scription of the benefits and potential problems of a hydrogen economy. （ 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）
29、 NG 5 Even if you have electricity and water, you still cannot produce hydrogen 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 hydrog
30、en economy. （ A） Y （ B） N （ C） NG 8 So far, there seems to be no solution 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 transp
31、ortation infrastructure will have to develop around it. 11 Concerning the 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
32、will be asked about what was said. Both the conversation and the questions 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） Look for a more expensive hotel. （ B） Go to
33、 another hotel by bus. （ C） Try to find a quiet place. （ D） Take a walk around the city. （ A） Theyre talking about nice children. （ B） The man has a house for sale. （ C） The woman lives in a nice house. （ D） The man has three children. （ A） In a hotel. （ B） At a dinner table. （ C） In the street. （ D
34、） At the mans house. （ A） Relatives. （ B） Roommates. （ C） Colleagues. （ D） Neighbors. （ A） 5:00. （ B） 5:15, （ C） 5:30 （ D） 5:45 （ A） He wants to have more sleep. （ B） His wife doesnt sleep well. （ C） Women need more sleep than men. （ D） He doesnt need as much sleep as his wife. （ A） A student. （ B）
35、A reporter. （ C） A visitor. （ D） A lecturer, （ A） To the school. （ B） To a friends house. （ C） To the post office. （ D） Home. （ A） To take much exercise. （ B） To eat less fats and sugars. （ C） To work hard. （ D） To have surgery. （ A） Because they want to keep fit. （ B） Because they want to look plea
36、sant. （ C） Because they are misled by doctors. （ D） Both A and B. （ A） People think too much of their appearance. （ B） Surgery is the fastest way of losing weight. （ C） Being on a diet is a safe way of losing weight. （ D） There is not a sure way of losing weight yet. （ A） From Monday to Friday, 8:30
37、-5:00. （ B） From Monday to Friday, 3:00-6:30. （ C） 6 days a week. （ D） 15 hours a week. （ A） Hairdresser. （ B） Shop assistant. （ C） Cook. （ D） Shorthand typist. （ A） Cook. （ B） Shorthand typist. （ C） Shop assistant. （ D） None of the above. （ A） Contact with the employers directly. （ B） Waiting for t
38、omorrows program. （ C） Call the Radio Station. （ D） Each of the above will be OK. 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 only once. After you hear a question, y
39、ou must choose the best answer from the four choices marked A, B, C and D. （ A） Eating some salad. （ B） Having a sandwich. （ C） Reading a book. （ D） Drinking coffee. （ A） By asking the waiter for advice. （ B） By asking the speaker for advice. （ C） By pointing at some pictures in the menu. （ D） By po
40、inting at the speakers food. （ A） Because it was on a special plate. （ B） Because they thought it was a kind of soup. （ C） Because they liked to drink chilly sauce. （ D） Because they thought it was vinegar. （ A） They are delighted because they can enjoy the scenery while driving. （ B） They are frigh
41、tened because traffic accidents are frequent. （ C） They are irritated because the bridge is jammed with cars. （ D） They are pleased because it saves them much time. （ A） They dont have their own cars to drive to work. （ B） Many of them are romantic by temperament. （ C） Most of them enjoy the drinks
42、on the boat. （ D） They tend to be more friendly to each other. （ A） Many welcome the idea of having more bars on board. （ B） Many prefer the ferry to maintain its present speed. （ C） Some suggest improving the design of the deck. （ D） Some object to using larger luxury boats. （ A） Saves more than 15
43、,000 lives each year. （ B） Reduces road accidents by more than half. （ C） Reduces the death rate in traffic accidents. （ D） Saves lives while driving at a speed up to 30 miles per hour. （ A） Wear a seat belt each time he drives. （ B） Stop children riding in the front seat. （ C） Make the front seat p
44、assenger wear a seat belt. （ D） Make the front seat children under 14 wear a seat belt. （ A） Someone who is under 14. （ B） Someone who is backing into a parking space. （ C） Someone who is delivering and collecting letters. （ D） Someone who is picking up the children from the local school. （ A） Wear
45、a seat belt for health reasons. （ B） Wear no seat belt for health reasons. （ C） Get a valid medical certificate before wearing a seat belt. （ D） Pay a fine rather than wear a seat belt. Section C Directions: In this section, you will hear a passage three times. When the passage is read for the first
46、 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 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 th
47、ese blanks, you can either use the exact words you have just heard or write down the 36 Today, American filmmakers produce movies with few restraints about violence, sexuality and adult language. But this was not always the case. The Motion Picture Association of America is the major movie organizat
48、ion that first formed in 1922. The organization helps【 B1】 _movies internationally, decides on 【 B2】 _systems, and deals with public relations for the movie industry. When it was first started by the Hollywood production【 B3】 _, the organization was called the Motion Picture Producers and Distributo
49、rs of America. The group was【 B4】 _called the Hays Office because of its director, Will Hays. This group developed the Motion Picture Production Code in 1930. The aim was for the film industry and not the government to decide what was【 B5】 _acceptable to show in movies. The Hays Office【 B6】 _each film before it could receive permission to be 【 B7】 _. The production code was very clear about【 B8】 _including crimes and sex. For example, movies could not s
