1、大学英语六级模拟试卷 790及答案与解析 一、 Part I Writing (30 minutes) 1 Directions: For this part, you are allowed 30 minutes to write a letter on behalf of the Students Union and the Academic Lectures Association to invite a visiting foreign professor, David, to deliver a presentation to the students in your univers
2、ity. You are NOT allowed to include the name of your university in this letter. You should write at least 150 words following the outline given below. 1. 对这位知名的外籍教授的到来表示欢迎 2表达希望该教授就某个话题在学校进行讲座的希望和对 讲座的一些基本设想 3希望教授可以接受邀请，并对教授的宝贵时间表示感谢 二、 Part II Reading Comprehension (Skimming and Scanning) (15 minut
3、es) 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 1-4, mark： Y (for YES) if the statement agrees with the information given in the passage; N (for NO) if the statement contradicts the information give
4、n in the passage; NG (for NOT GIVEN) if the information is not given in the passage. 2 Hybrid Cars Have you pulled your car up to the gas pump lately and been shocked by the high price of gasoline? As the pump clicked past $20 or $30, maybe you thought about trading in your car for something that ge
5、ts better mileage. Or maybe youre worried that your car is contributing to the greenhouse effect. The auto industry has the technology to address these concerns. Its the hybrid car. Youre probably aware of hybrid cars because theyve been in the news a lot. Most automobile manufacturers have announce
6、d plans to manufacture their own versions. What makes it a “Hybrid“? Any vehicle is a hybrid when it combines two or more sources of power. In fact, many people have probably owned a hybrid vehicle at some point. For example, a moped (a motorized pedal bike) is a type of hybrid because it combines t
7、he power of a gasoline engine with the pedal power of its rider. Hybrid vehicles are all around us. Most of the locomotives we see pulling trains are diesel-electric hybrids. Cities like Seattle have diesel-electric(以柴油发动机发电的 ) busesthese can draw electric power from overhead wires or run on diesel
8、when they are away from the wires. Giant mining trucks are often diesel-electric hybrids. Submarines are also hybrid vehicles some are nuclear-electric and some are diesel-electric. The gasoline-electric hybrid car is a cross between a gasoline-powered car and an electric car. Hybrid Structure You c
9、an combine the two power sources found in a hybrid car in different ways. One way, known as a parallel hybrid, has a fuel tank, which supplies gasoline to the engine. But it also has a set of batteries that supplies power to an electric motor. Both the engine and the electric motor can turn the tran
10、smission at the same time, and the transmission then turns the wheels. By contrast, in a series hybrid the gasoline engine turns a generator, and the generator can either charge the batteries or power an electric motor that drives the transmission. Thus, the gasoline engine never directly powers the
11、 vehicle. Why Build Such a Complex Car? You might wonder why anyone would build such a complicated machine when most people are perfectly happy with their gasoline-powered cars. The reason is twofold: to reduce tailpipe emissions and to improve mileage. These goals are actually tightly interwoven. E
12、volution of the Hybrid The hybrid is a compromise. It attempts to significantly increase the mileage and reduce the emissions of a gas-powered car while overcoming the shortcomings of an electric car. The Problem with Gas-powered Cars To be useful to you or me, a car must meet certain minimum requir
13、ements. The car should be able to: -Drive at least 300 miles (482 km) between re-fueling -Be refueled quickly and easily -Keep up with the other traffic on the road A gasoline car meets these requirements but produces a relatively large amount of pollution and generally gets poor gas mileage. An ele
14、ctric car, on the other hand, produces almost no pollution, but it can only go 50 to 100 miles (80 to 161 km) between charges. And the problem has been that it is very slow and inconvenient to recharge. A drivers desire for quick acceleration causes our cars to be much less efficient than they could
15、 be. You may have noticed that a car with a less powerful engine gets better gas mileage than an identical car with a more powerful engine. Just look at the window stickers(有图形或文字的粘贴标鉴 ) on new cars at a dealership for a city and highway mph comparison. The amazing thing is that most of what we requ
16、ire a car to do uses only a small percentage of its horsepower! When you are driving along the freeway at 60 mph (96.6 kph), your car engine has to provide the power to do three things: -Overcome the aerodynamic drag caused by pushing the car through the air; -Overcome all of the friction in the car
17、s components such as the tires, transmission, axles and brakes; -Provide power for accessories like air conditioning, power steering and headlights. For most cars, doing all this requires less than 20 horsepower! So, why do you need a car with 200 horsepower? So you can “floor it“, which is the only
18、 time you use all that power. The rest of the time, you use considerably less power than you have available. Smaller Engines are More Efficient Most cars require a relatively big engine to produce enough power to accelerate the car quickly. In a small engine, however, the efficiency can be improved
19、by using smaller, lighter parts, by reducing the number of cylinders and by operating the engine closer to its maximum load. There are several reasons why smaller engines are more efficient than big ones: -The big engine is heavier than the small engine, so the car uses extra energy every time it ac
20、celerates or drives up a hill. -The pistons(活塞 ) and other internal components are heavier, requiring more energy each time they go up and down in the cylinder. The displacement of the cylinders is larger, so more fuel is required by each cylinder. Bigger engines usually have more cylinders, and eac
21、h cylinder uses fuel every time the engine fires, even if the car isnt moving. This explains why two of the same model cars with different engines can get different mileage. If both cars are driving along the freeway at the same speed, the one with the smaller engine uses less energy. Both engines h
22、ave to output the same amount of power to drive the car, but the small engine uses less power to drive itself. Hybrid Performance The key to a hybrid car is that the gasoline engine can be much smaller than the one in a conventional car and therefore more efficient. But how can this smaller engine p
23、rovide the power your car needs to keep up with the more powerful cars on the road? Lets compare a car like the Chevy Camaro, with its big V8 engine, to our hybrid car with its small gas engine and electric motor. The engine in the Camaro has more than enough power to handle any driving situation. T
24、he engine in the hybrid car is powerful enough to move the car along on the freeway, but when it needs to get the car moving in a hurry, or go up a steep hill, it needs help. That “help“ comes from the electric motor and battery this system steps in to provide the necessary extra power. The gas engi
25、ne on a conventional car is sized for the peak power requirement (those few times when you floor the accelerator pedal). In fact, most drivers use the peak power of their engines less than one percent of the time. The hybrid car uses a much smaller engine, one that is sized closer to the average pow
26、er requirement than to the peak power. 2 This passage gives a general description of the advantages and disadvantages of a hybrid auto- mobile. （ A） Y （ B） N （ C） NG 3 The series hybrid vehicle is sometimes directly powered by the gasoline engine. （ A） Y （ B） N （ C） NG 4 In most cases, what we requi
27、re a car to do uses only a small percentage of its horse power. （ A） Y （ B） N （ C） NG 5 With a view to improving hybrid performance, you can use composite materials to reduce weight. （ A） Y （ B） N （ C） NG 6 We want to build a hybrid car partly because it has lower _ than a gasoline- powered one. 7 I
28、f the hybrid car needs to go up a steep hill, it can get extra power from _. 8 Compared with a big engine, a small one can improve the gas mileage by running closer to its _. 9 A motorbike is a type of hybrid because it uses two _ to run. 10 One of the advantages of the gasoline car over the electri
29、c one is that the gasoline car is relatively _ to refuel. 11 There are two different hybrid modes: one is called _ and the other series. 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
30、 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） He is confident. （ B） He is worried. （ C） He is bo
31、red. （ D） He is angry. （ A） Compare her own paper with others. （ B） Watch out for the usual typing mistakes. （ C） Have someone else type her paper. （ D） Ask another person to check her work. （ A） Jealous. （ B） Indignant. （ C） Negative. （ D） Proud. （ A） She doesnt like the way the professor lectures.
32、 （ B） Shes having a hard time following the professors lectures. （ C） She is not interested in course. （ D） Shes having difficulty with the heavy reading assignments. （ A） Hes going to help the woman bake her cake. （ B） He is going to buy some cake. （ C） He is going to sweep the study floor. （ D） He
33、 will get a broom and dust pan to clean up the floor. （ A） The man can have his camera fixed here. （ B） The woman will probably fix the mans camera herself. （ C） The man will buy a new camera. （ D） The woman suggests that the camera should have been brought in earlier. （ A） She thinks big parties ar
34、e too impersonal. （ B） She would like to invite friends to a big party. （ C） She feels she has to spend a lot of money in holding big parties. （ D） She would like to be invited to small parties. （ A） He thinks that they are of inferior quality. （ B） He thinks that they are a bargain. （ C） He thinks
35、that they are overpriced. （ D） He thinks that they can be purchased at a cheaper price elsewhere. （ A） He has finished the first draft. （ B） He has just got started. （ C） He has finished the main body. （ D） He has handed the paper in. （ A） Strict and picky. （ B） Responsible and nice. （ C） Helpful an
36、d patient. （ D） Responsible but too direct. （ A） Have dinner with him. （ B） Write the paper for him. （ C） Go to classes with him. （ D） Help him with the paper. （ A） She is worried about the safety in those countries. （ B） She is a little worried about her health. （ C） She is afraid she will spend al
37、l her money. （ D） She doesnt like those countries very much. （ A） The terrible tsunami. （ B） Faint due to the hot weather. （ C） The dangerous insects. （ D） The terrorists. （ A） A lot of pills and some cream. （ B） A great deal of cash. （ C） Some cream and several thick clothes. （ D） Some special equi
38、pments. （ A） She is still hesitating about it. （ B） She will change another place for a holiday. （ C） She will go on her trip as planned. （ D） She decides to stay at home. Section B Directions: In this section, you will hear 3 short passages. At the end of each passage, you will hear some questions.
39、 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） The quicker it vibrates, the greater the frequency of sound it produces. （ B） The slower it vibrates, the higher the frequency of
40、sound it produces. （ C） The quicker it vibrates, the lower the frequency of sound it produces. （ D） The frequency of sound it produces is not in proportion to the speed it vibrates. （ A） Those with frequencies lower than 20 hertz. （ B） Those with frequencies about 21,000 hertz. （ C） Those with frequ
41、encies lower than 20,000 hertz. （ D） Those with frequencies higher than 20,000 hertz. （ A） A bat caught the insect in midair and ate it. （ B） Dolphins clicking sounds bounced off the fish and back to it. （ C） A person heard an echo when he shouted into the valley. （ D） A dog heard his owners whistle
42、 because he used ultrasound. （ A） Pre-law students. （ B） A group of students. （ C） The audience. （ D） The faculty. （ A） Typing skills. （ B） Experience in journalism. （ C） Being a qualified student. （ D） Lots of money. （ A） Two days later. （ B） In a couple of days. （ C） Immediately after the meeting.
43、 （ D） Tomorrow. （ A） At school. （ B） At home. （ C） At Youth Clubs. （ D） At Youth Centers. （ A） They develop their identities within peer groups. （ B） They receive informal education. （ C） They perform voluntary community services. （ D） They participate in all kinds of extracurricular activities. （ A
44、） About four million. （ B） About seven million. （ C） About five million. （ D） About six million. （ A） Sport events. （ B） Cultural activities. （ C） Counseling. （ D） Creative activities. Section C Directions: In this section, you will hear a passage three times. When the passage is read for the first
45、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 the
46、se blanks, you can either use the exact words you have just heard or write down the 36 Muslim Sudan is one of the Islamized【 B1】 _ regions. In East Africa musical forms showing Arab or Islamic influence are found even far【 B2】 _ , for instance in southern Uganda, not only along the Indian Ocean coas
47、t. Several musical【 B3】 _ of Arab introduction can be seen in these parts, the one-string fiddle being the most visible example, On the other hand,【 B4】 _ areas of black Africa are virtually free from Arab or Islamic influence. The traditional schools for boys found in west central Africa, with thei
48、r【 B5】 _ dances and music, are independent black African【 B6】 _ and in no way to be related to Muslim【 B7】 _ It is now widely【 B8】 _ that African music/dance in various parts of the continent has constantly undergone decisive changes in history.【 B9】 _ Nor is African music always ethnic in the sense
49、 ethnomusicology would have it. Music forms and traits are not rigidly linked to ethnic groups;【 B10】 _ Ethnic groupings have themselves been in a state of continuous flux and musical traits and fashions have been exchanged across ethnic and linguistic boundaries.【 B11】_ and even so may present a fragmented and perplexing picture. 37 【 B1】 38 【 B2】 39 【 B3】 40 【 B4】 41 【 B5】 42 【 B6】 43 【 B7】 44 【 B8】 45 【 B9】 46 【 B10】 47 【 B11】 Section
