1、大学英语四级模拟试卷 768(无答案)一、Part I Writing (30 minutes)1 For this part, you are allowed 30 minutes to write an essay entitled Living Expenditure of College Students. You should write at least 120 words following the out line given below in Chinese: 1. 大学生的生活费用安排发生变化; 2. 产生这些变化的原因是什么; 3. 你的看法。二、Part II Read
2、ing 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 NO) i
3、f 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 ECONOMYIt seems-like every day there is a new announcement in the news about automobiles powered by fuel cells. The promises are great, since fuel cells h
4、ave 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 on our depe
5、ndence 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 cleaner hydrogen
6、 future.Problems with the fossil fuel economyWhile 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:Carbon monoxide, a po
7、isonous gasNitrogen oxides, the main source of urban smogUnburned hydrocarbons, the main source of urban ozoneEnvironmental 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 well fire can creat
8、e a huge mess.Global warmingThe 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 that affect everyone on
9、 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 has little choice but t
10、o pay the higher price.Advantages of the hydrogen economyThe 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 hydrogen is used in a fuel
11、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 hydrogen adds no greenhouse gase
12、s 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 and its oil reserves.Distrib
13、uted 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 economy so significant, that the
14、 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 and tricky in its natural gaseous
15、 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 molecules to create pure hydrogen and oxyge
16、n. 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 hydrocarbons-molecules consisting of hydrogen an
17、d 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 course, slightly perverse(不正当的). You ar
18、e 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(转变) to the hydrogen economy.The interes
19、ting 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 enough electricity to separate hydrogen fr
20、om 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 produced in the United States comes from co
21、al 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 damsSolar cells Wind turbinesGeothermal power Wave and ti
22、dal powerCo-generationHow 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 the same volume of gasoline. However, solutions to
23、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 infrastructure will have to develop around it. The m
24、ain 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 sodium borohydride, then a station network could de
25、velop quickly; that sort of standardization is unlikely to happen rapidly, if history is any guide.Prospects for the futureYou will hear more and more about the hydrogen economy in the news in the Coming months, because the drumbeat is growing louder. The environmental problems of the fossil fuel ec
26、onomy 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 gasoline and reformers, fuel cells represent two majo
27、r 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.(A)Y(B) N(C) NG3 An oil spill can pose a big problem to th
28、e environment.(A)Y(B) N(C) NG4 Compared with other major industrialized countries, the United States depends more heavily on oil import.(A)Y(B) N(C) NG5 Even if you have electricity and water, you still cannot produce hydrogen everywhere.(A)Y(B) N(C) NG6 In the United States, most of the electricity
29、 is generated from coal or natural gas.(A)Y(B) N(C) NG7 We must derive hydrogen from renewable sources with a view to a pure hydrogen economy.(A)Y(B) N(C) NG8 So far, there seems to be no solution in sight as to how the hydrogen can be stored.(A)Y(B) N(C) NG9 Possible sources for the hydrogen are bo
30、th 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 the future of the hydrogen economy, the most obvious step we will take is _.Section ADirections: In this section, you
31、 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 will be a pause. During the pause, you must read the four c
32、hoices marked A, B, C and D, and decide which is the best answer.(A)The man wants to attend tomorrows show.(B) There arent any tickets left for tonights show.(C) There arent any tickets left for tomorrows show.(D)The man doesnt want to attend tomorrows show. (A)Detective stories.(B) Stories about fa
33、il escapes.(C) Love stories.(D)Stories about royal families. (A)It was a long lecture, but easy to understand.(B) It was not as easy as she had thought.(C) It was as difficult as she had expected.(D)It was interesting and easy to follow. (A)To put him through to the director.(B) To have a talk with
34、the director about his work.(C) To arrange an appointment for him with the director.(D)To go and see if the director can meet him right now. (A)Margaret wanted to return some magazines to the woman.(B) Margaret wanted to lend some magazines to the woman.(C) Margaret wanted to borrow some magazines f
35、rom the woman.(D)Margaret wanted to get some magazines back from the woman. (A)He doesnt care much about it.(B) He enjoys it very much.(C) He doesnt mind even though its tedious.(D)He hates working overtime. (A)The woman doesnt think it exciting to travel by air.(B) Theyll stay at home during the ho
36、lidays.(C) They are offered some plane tickets for their holidays.(D)Theyll be flying somewhere for their vacation. (A)Something went wrong with the bus.(B) She took somebody to hospital.(C) Something prevented her from catching the bus.(D)She came on foot instead of taking a bus. (A)An employee in
37、the city council at Birmingham.(B) Assistant Director of the Admissions Office.(C) Head of the Overseas Students Office.(D)Secretary of Birmingham Medical School.(A)Nearly fifty percent are foreigners.(B) About fifteen percent are from Africa.(C) A large majority are from Latin America.(D)A small nu
38、mber are from the Far East.(A)She will have more contact with students.(B) It will bring her capability into fuller play.(C) She will be more involved in policy-making.(D)It will be less demanding than her present job.(A)The balance of work and study.(B) The financial aid.(C) Education and good job.
39、(D)The tuition.(A)To apply for financial aid.(B) To apply for some sort of assistantship.(C) To cut down on his classes and work more hours.(D)To study full time and work full time.(A)Theres not enough financial aid available.(B) A good education is of great importance.(C) More students worry about
40、their school fees each year.(D)The man wishes to be a financial consultant.(A)See if he qualifies for a student loan.(B) Make a proposal to the government.(C) Start to save up to pay for his kids to go to school.(D)Take a semester off from school to earn more money.Section BDirections: In this secti
41、on, 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, you must choose the best answer from the four choices marked A, B, C and D.(A)When the Moon passes the Earth.(B) When
42、the Moon passes the Sun.(C) When the Moon goes away from the Earth.(D)When the Moon passes between the Sun and the Earth.(A)Northern Canada.(B) Central Russia.(C) Southern America.(D)Western Mongolia.(A)Two minutes.(B) Three minutes.(C) Ten minutes.(D)Two hours.(A)It took place iii Chicago in 1859.(
43、B) Four cars powered by petrol took part in it.(C) Only one carmaker, Henry Ford was unable to take part in it.(D)Henry Ford had no car to take part in it. (A)Workers have to walk up and down along the assembly line.(B) Workers neednt move while the produce is moved.(C) Many people accepted the idea
44、 of an assembly line at Henry Fords time.(D)Henry Fords friends supported the idea of an assembly line. (A)Because he persuaded his workers to buy Model-T cars.(B) Because Model-T was ugly and always black.(C) Because Model-T was cheap but beautiful.(D)Because Model-T was cheap and simple and he inc
45、reased his workers pay to buy cars. (A)They built the pyramid in honor of the gods.(B) They built the pyramid as their tombs.(C) They wanted the world to remember them.(D)Both B and C.(A)100,000.(B) 10,000.(C) 2,300,000.(D)230,000.(A)They built the pyramids with the help of ancient machines.(B) They
46、 built the pyramids with only human labors.(C) They built the pyramids with the help of aliens.(D)It is still unknown now.(A)There are many pyramids along the Nile River.(B) To build he pyramid of Khufu, 100,000 men worked for twelve years.(C) The biggest pyramid in Mexico is almost 2,000 years old.
47、(D)The biggest pyramid in Mexico is called the Pyramid of the Sun.Section CDirections: 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 t
48、o 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 heard or write down the 37 You probably have noticed that pe
49、ople express similar ideas in different ways, depending on the situation they are in. This is very 【B1】_ . All languages have two general levels of 【B2】_ : a formal level and an in formal level. English is no 【B3】 _ . The difference in these two levels is the situation in which you use a 【B4】 _ level. Formal language is the kind of language you find in textbooks, 【B5】 _ books, and in business letters. You would also use formal English in compositions an
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