单选题Believe it or not, optical illusion (错觉) can cut highway crashes. Japan is a case in point. It has reduced automobile crashes on some roads by nearly 75 percent using a simple optical illusion. Bent stripes, called chevrons (人字形) painted on the roads make drivers think that they are driving faster than they really are, and thus drivers slow down. Now the American Automobile Association Foundation for Traffic Safety in Washington D.C. is planning to repeat Japan's success. Starting next year, the foundation will paint chevrons and other patterns of stripes on selected roads around the country to test how well the patterns reduce highway crashes. Excessive speed plays a major role in as much as one fifth of all fatal traffic accidents, according to the foundation. To help reduce those accidents, the foundation will conduct its tests in areas where speed related hazards are the greatest curves, exit slopes, traffic circles, and bridges. Some studies suggest that straight, horizontal bars painted across roads can initially cut the average speed of drivers in half. However, traffic often returns to full speed within months as drivers become used to seeing the painted bars. Chevrons, scientists say, not only give drivers the impression that they are driving faster than they really are but also make a lane appear to be narrower. The result is a longer lasting reduction in highway speed and the number of traffic accidents.

单选题Centuries ago, man discovered that removing moisture from food helps to preserve it, and that the easiest way to do this is to expose the food to sun and wind. All foods contain water--cabbage and other leaf vegetables contain as much as 93% water, potatoes and other root vegetables 80% , lean meat 75% and fish anything from 80% to 60% depending on how fatty it is. If this water is removed, the activity of the bacteria(细菌) which cause food to go bad is checked. Nowadays most foods are dried mechanically. The conventional method of such dehydration(脱水) is to put food in chambers through which hoi air is blown at temperatures of about 110°C at entry to about 43°C at exit. This is the usual method for drying such things as vegetables, minced meat, and fish. Liquids such as milk, coffee, tea, soups and eggs may be dried by pouring them over a heated horizontal steel cylinder or by spraying them into a chamber through which a current of hot air passes. In the first case, the dried material is scraped off the roller as a thin film which is then broken up into small, though still relatively coarse flakes. In the second process it falls to the bottom of the chamber as a fine powder. Dried foods 'take up less room and weigh less than the same food packed in cans or frozen, and they do not need to be stored in special conditions. For these reasons they are invaluable to climbers, explorers and soldiers in battle, who have little storage space. They are also popular with housewives because it takes so little time to cook them.

单选题Whyisthewomanwordedaboutthewashingmachine?

单选题Whatwillthemandotonight?A.Hewillreturntohishometown.B.Hewillplaytennis.C.Hewilljointhewomanfordinner.D.Hewillgotoacoffeeshopwiththewoman.

单选题In recent years, more and more foreigners are involved in the teaching programs of the United States. Both the advantages and the disadvantages of using foreign faculty (26) teaching positions have to be (27) , of course. It can be said that the foreign (28) that makes the faculty member from abroad an asset also (29) problems of adjustment, both for the university and for the (30) The foreign research scholar usually (31) himself in the laboratory as means of protection; however, what he needs is to be fitted (32) a highly organized university system quite different from (33) at home. He is faced in his daily work (34) differences in philosophy, arrangements of courses and methods of teaching. Both the visiting professor and his students lack a (an) (35) ground in each other' scultures. Some (36) of what is already in the minds of American students is (37) for the foreign professor. While helping him to (38) himself to his new environment, the university must also (39) certain adjustments in order to (40) full advantage of what the newcomer can (41) It isn't always known how to make (42) use of foreign faculty, especially at smaller colleges. This is thought to be a field (43) further study is called (44) . The findings of such a study will be of (45) to colleges and universities with foreign faculty.

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单选题Concerning the drug quinine, which of the following is NOT true?

单选题 {{I}}Questions 11-13 are based on the following passage about the transportation in the future.{{/I}}

单选题 Questions 23～25 are based on the following conversation.

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单选题All of the following statements are true EXCEPT that______ .

单选题{{I}}Questions 14 - 17 are based on the following dialogue about redwood.{{/I}}

单选题The first sentence in paragraph two means that the conclusions of the experts are ______.

单选题Most of us can't remember our first vaccination, a common practice of preventing us against diseases. Chances are, it was a shot filled with a drug formula—just enough to produce a mild infection but not the full-blown disease. Immunizing, or preventing people against some diseases in this way has worked reasonably well for more than a century, but scientists think they can do better by using genetically engineered plants. We all know that eating fruits and vegetables is good for us, but within the next decade we could be eating as a way to deliver drugs that keeps off epidemic diseases or that treat various chronic conditions. "The idea of vaccinating people with edible plants is very new," says Dwayne Kirk of the Boyce Thompson Institute for Plant Research in Ithaca, New York, "But it's a lot friendlier than injections." Potatoes and tomatoes seem for now to be the most efficient vehicles for the new approach. Instead of mixing viral or bacterial DNA in a formula for injection, for example, scientists could insert it into soil bacteria. When the bacteria are taken-up by the plant, the DNA material gets into the plant. Another method of getting genes into plants is to coat tiny particles of metals such as gold with foreign DNA, then shoot the particles directly into plant cells. Either way, the plant's cells start to produce whatever proteins the new genes are designed to make. Immunization begins when the plant or its fruit is eaten, prompting the body to produce the appropriate antibodies. The technique does not have to be limited to infectious diseases, however. It may even be useful for conditions such as Type I diabetes. For such patients, eating genetically engineered plants could eventually train the body's defenses, all without the bother—or risk—of a needle. Plant-based vaccines are particularly attractive for Third World countries, where storage and distribution of drugs are a problem. Eventually, people in these areas may inoculate themselves against diseases simply by growing a crop of genetically engineered fruits or vegetables and eating a few several times a year.

单选题You will hear 10 short dialogues. For each dialogue, there is one question and four possible answers. Choose the correct answer—A, B, C or D, and mark it in your test booklet. You will have 15 seconds to answer the question and you will hear each dialogue ONLY ONCE.