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单选题He is one of those men who dislike work Uintensely/U and will do anything to avoid it.
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单选题She was grateful to him for being so good to her.
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单选题I have heard this {{U}}tune{{/U}} before, but I don't know the words to the song.
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单选题Pesticides (杀虫剂) Why do pesticides(杀虫剂)fit into the picture of environmental disease? We have seen that they now pollute soil, water and food, that they have the power to make our streams fishless and our gardens and woodlands silent and birdless. Man, however much he may like to pretend the contrary, is part of nature. Can he escape a pollution that is now so thoroughly distributed throughout our world? We know that even single exposures(暴露)to these chemicals, if the amount is large enough, can cause extremely severe poisoning. But this is not the major problem. The sudden illness or death of farmers, farm workers and others exposed to sufficient quantities of pesticides are very sad and should not occur. For the population as a whole, we must be more concerned with the delayed effects of absorbing small amounts of the pesticides that invisibly pollute our world. Responsible public health officials have pointed out that the biological effects of chemicals are cumulative(积累的) over long periods of time, and that the danger to the individual may depend on the sum of the exposures received throughout his lifetime. For these very reasons the danger is easily ignored. It is human nature to shake off(摆脱) what may seem to us a threat of future disaster. "Men are naturally most impressed by diseases which have obvious signs", says a wise physician, Dr. Rene Dubos, "yet some of their worst enemies slowly approach them unnoticed. /
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单选题She's extremely competent and industrious
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单选题The article sketched the major events of the decade.
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单选题The police arrested the suspect yesterday and {{U}}released{{/U}} him this morning.
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单选题During an earthquake in China in 1975, some cows had "earthquake nerves" and some remained calm.
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单选题下面的短文有15处空白,请根据短文内容为每处空白确定1个最佳选项。 Car Thieves Could Be Stopped Remotely(遥远地) Speeding off(超速行驶) in a stolen car, the thief thinks he has got a great catch. But he is in a nasty surprise. The car is fitted with a remote immobilizer(使车辆不能调动的装置), and a radio signal from a control center miles away will ensure that once the thief switches the engine {{U}}(51) {{/U}}, he will not be able to start it again. For now, such devices {{U}}(52) {{/U}} only available for fleets of trucks and specialist vehicles used on construction sites. But remote immobilization(使车辆不能调动) technology could soon start to trickle(慢慢地移动) down to ordinary cars, and {{U}}(53) {{/U}} be available to ordinary cars in the UK {{U}}(54) {{/U}} two months. The idea goes like this. A control box fitted to the car incorporates {{U}}(55) {{/U}} iniature cellphone (移动电话,手机), a microprocessor and memory, and a GPS satellite positioning receiver. {{U}}(56) {{/U}} the car is stolen, a coded cellphone signal will tell the unit to block the vehicles engine management system and prevent the engine {{U}}(57) {{/U}} restarted. There are even plans for immobilizers {{U}}(58) {{/U}} shut down vehicles on the move, though there are fears over the safety implications of such a system. In the UK, an array of technical fixes is already making {{U}}(59) {{/U}} harder for car thieves. The pattern of vehicles crime has changed, says Martyn Randall of Thatcham, a security research organization based in Berkshire that is funded in part {{U}}(60) {{/U}} the motor insurance industry. He says it would only take him a few minutes to {{U}}(61) {{/U}} a novice(新手,初学者) how to steal a car using a bare minimum of tools. But only if the car is more than 10 years old. Modern cars are a far tougher (艰苦的) proposition (任务), as their engine management computer will not {{U}}(62) {{/U}} them to start unless they receive a unique ID code beamed out by the ignition(点火) key. In the UK, technologies like this {{U}}(63) {{/U}} achieve a 31 per cent drop in vehicle-related crime since 1997. But determined criminals are still managing to find other ways to steal cars. Often by getting hold of the owners keys in a burglary (夜窃行为;盗窃). In 2000, 12 per cent of vehicles stolen in the UK were taken using the owners keys double the previous years figure. Remote-controlled immobilization system would {{U}}(64) {{/U}} a major new obstacle in the criminals way by making such thefts pointless. A group that includes Thatcham, the police, insurance companies and security technology firms have developed standards for a system that could go on the market sooner than the {{U}}(65) {{/U}} expects.
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单选题In previous times, when fresh meat was inadequate, pigeons were kept by many households as a source of food. A. in short store B. in short provision C. in short reserve D. in short supply
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单选题About one million Americans are diagnosed {{U}}annually{{/U}} with skin cancer. A. every year B. severely C. actively D. every month
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单选题You must shine your shoes.
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单选题In recent years a new farming revolution has begun, one that involves the manipulation of life at a fundamental level—the gene. The study of genetics has (51) a new industry called biotcehnology. As the name suggests, it (52) biology and modern technology through such techniques as genetic engineering. Some of the new biotech companies specialize in agriculture and are working feverishly to (53) seeds that give a high yield, that (54) diseases, drought and frost, and that reduce the need for hazardous chemicals, If such goals could be achieved, it would be most (55) . But some have raised concerns about genetically engineered crops. In nature, genetic diversity is created within certain (56) . A rose can be crossed with a different kind of rose, but a rose will never cross with a potato. Genetic engineering, (57) usually involves taking genes from one species and inserting them into another in an attempt to transfer a desired characteristic. This could mean, for example, selecting a gene which leads to the production of a chemical with anti-freeze (58) from an artic fish, and inserting it into a potato or strawberry to make it frost, resistant, in essence, then, biotechnology allows humans to (59) the genetic walls that separate species. Just like the green revolution, (60) some call the gene revolution contributes to the problem of genetic uniformity-some say even more so (61) geneticists can employ techniques such as cloning and (62) culture (培养) and processes that produce perfectly (63) copies. Concerns about the erosion of biodiversity, therefore, remain. Genetically altered plants, however, raise new (64) ,such as the effects that they may have on us and the environment. "We are tlying blindly into a new era of agricultural biotechnology with high hopes, few constraints, and little idea of the potential (65) ," said science writer Jeremy Rifkin.
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单选题I feel regret about what"s happened.
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单选题The football team, for the most part, were confident of winning the match.A. mostlyB. partlyC. onlyD. really
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单选题“What do you mean by that”Paul asked Usharply /U
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单选题{{B}}第二篇{{/B}} Flying the Hypert Skies A little airplane has given new meaning to the term "going hyper. " The Hyper-X recently broke the record for air-breathing jet planes when it traveled at a hypersonic speed of seven times the speed of sound. That's about 5,000 miles per hour. At this speed, you'd get around the world -- flying along the equator (赤道) -- in less than 5 hours. The Hyper-X is an unmanned,experimental aircraft just 12 feet long. It achieves hypersonic (超音速的) speed using a special sort of engine known as a scramjet. It may sound like something from a comic book,but engineers have been experimenting with scramjets since the 1960s. For an engine to burn fuel and produce energy, it needs oxygen. A jet engine, like those on passenger airplanes, gets oxygen from the air. A rocket engine typically goes faster but has to carry its own supply of oxygen. A scramjet (紧急刹车) engine goes as fast as a rocket, but it doesn't have to carry its own oxygen supply. A scramjet's special design allows it to obtain oxygen from the air that flows through the engine. And it does so without letting the fast-moving air put out the combustion (燃烧) flames. However, a scramjet engine works properly only at speeds greater than five times the speed of sound. A booster rocket carried the Hyper-X to an altitude of about 100,000 feet for its test flight. The aircraft's record-beating flight lasted just 11 seconds. Although the little plane's self-powered flight lasted only 11 seconds, that brief journey on March 27 makes a major milestone on the way to a new breed of very fast airplanes, comments Werner J. A. Dahm of the University of Michigan in Ann Arbor. In the future, engineers predict, airplanes equipped with scramjet engines could transport cargo quickly and cheaply to the brink of space. Such hypersonic jets could potentially carry passengers anywhere in the world in just a few hours. Out of the three experimental Hyper-X aircrafts built for NASA, only one is now left. The agency has plans for another 11-second hypersonic flight, this time at 10 times the speed of the sound.
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单选题You startled me when you shouted.
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单选题Two scientists lost their lives during the second eruption of Mount Saint Helens.
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单选题Some people would like to do shopping on Sundays since they expect to pick up wonderful articles in the market.
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