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单选题(2007) The washing machine needs______before it can be used.
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单选题He wasn"t ______ for what had happened.
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单选题According to McWhorter, the decline of formal English ______.
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单选题Researchers have recently found a connection between disease and stressful situations. To test this theory, psychologists are trying to find a link between the brain and the immune system. The immune system in our bodies fights the bacteria and viruses which cause disease. Therefore, whether or not we are likely to get various diseases depends on how well our immune system works. Biologists used to think that the immune system was a separate, independent part of our bodies. Recently, however, they have found that our brain can affect our immune system. This discovery indicates that there may be a connection between emotional factors, such as stress or depression, and illness. Although many doctors in the past suspected a connection between emotional factor and disease, they had no proof. Scientists have only recently discovered how the brain and the immune system function. Before this, no one could see a link between them. As a result, medical science never seriously considered the idea that psychological factors could cause disease. Several recent studies showed a connection between stress and illness, for example, researchers went to an American military school to study the students. They found that the sick students there had a lot of academic pressure and wanted to achieve, but they were not very good students. In a similar study, researchers studied a group of student nurses and found that the nurses who developed cold sores were the ones who described themselves as generally unhappy people. In addition to these results, which support their theory, researchers are also looking for proof that stress can damage the immune system. Researchers studied recently bereaved people, i.e. , people whose loved ones have just died, because they are more likely to become ill or die. By examining the immune system of recently bereaved people, the researchers made an important discovery. They examined some white blood cells which are an important part of the immune system. They were not functioning properly. The fact that they were not working correctly indicates that severe psychological stress, such as a loved one"s death, may damage an important part of our immune system. There is still no positive proof of a connection between the immune system and psychological factors. Researchers also say that the results of the studies on bereaved people could have a different explanation. For example, bereaved people often sleep and eat less than normal, or may drink alcohol or take medication. These factors can also affect the immune system. More research is needed to clearly establish the connection between the immune system and psychological factors.
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单选题The mother rejected my suggestion that she ______ her daughter the next week. A. would meet B. shall meet C. meet D. met
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单选题In many places water is becoming scarcer. Treating it as a right makes the scarcity worse. Ideally, efficient water use would be encouraged by charging for it, but attempts to do so have mostly proved politically impossible. A more practicable alternative is a system of tradable waterusage rights. As our explains, many water problems have global causes: population growth, climate change, urbanization and, especially, changing diets. It takes 2,000 liters of water to grow a kilo of vegetables but 15,000 liters to produce a kilo of beef—and people are eating more meat. The problems also have global implications. Without a new green revolution, farmers will need 60% more water to feed the 2 billion extra people who will be born between now and 2025. Yet there is, globally, no shortage of water. Unlike other natural resources (such as oil), water cannot be used up. It is recycled endlessly, as rain, snow or evaporation. On average, people are extracting for their own uses less than a tenth of what falls as rain and snow each year. The central problem is that so much water is wasted, mainly by farmers. Agri-culture uses three-quarters of the world's water. Because water is usually free, thirsty crops like alfalfa (苜蓿) are grown in arid California. Wheat in India and Brazil uses twice as much water as wheat in America. Dry countries like Pakistan export textiles though a 1 kg bolt of cloth requires 11,000 liters of water. Any economist knows what to do: price water to reflect its value. But decades of trying to do that for agriculture have run into powerful resistance from farmers. They reject scarcity pricing for the reason that water falls from the skies. No government owns it, so no government should charge for it. There is a way out. Australian farmers have the right to use a certain amount of water free. They can sell that right to others. But if they want more water themselves, they must buy it from a neighbor. The result of this trading is a market that has done what markets do: allocate resources to more productive use. Australia has endured its worst drought in modern history in the past ten years. Water supplies in some farming areas have fallen by half. Yet farmers have responded to the new market signals by switching to less thirsty crops and kept the value of farm output stable. Water productivity has doubled. Australia's system overcomes the usual objections because it confirms farmers' rights to water and lets them have much of it for nothing.
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单选题What do gentlemen now do when a lady gets on a crowded bus or train?
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单选题If Alaska ______ to the United States, perhaps Russian ______ there now. A. were not to be sold; is spoken B. were not sold; is spoken C. had not been sold; would be spoken D. had not been sold; was spoken
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单选题The ______ over there is an Australian. [A] standing man [B] man stood [C] man standing
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单选题What message does the author try to convey in this passage?
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单选题Three fundamental aspects of (forest conversation) are the protection of immature trees, the use (of proper) harvesting methods, and (provide) for an environment (that supports) reproduction.
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单选题The banknotes which had fooled many bank tellers were discovered to be ______. A. artificial B. genuine C. counterfeit D. faulty
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单选题 Many people think there is no need to take special care over home security. "I'm all right, I'm insured." Maybe--if you're fully insured. Even then you can never recover the real value you place upon your possessions. But you can't insure against the upset and unhappiness that we all feel if our homes are seriously damaged by some stranger, our windows and doors smashed, our precious possessions ruined. "It won't happen to me." Won't it? A home is broken into almost every minute of the day. Thefts of all kinds, including cars and property stolen, happen twice as frequently. "I've nothing worth stealing." You may think not. But in fact every one has something worth a thief's attention. And we all have things of special value to us even if they're worth little or nothing in cash terms. "I'm only a tenant here." The thief doesn't care whether you're a tenant or an owner-occupier. You're just as likely to be robbed. Have a word with the owner of the house ff you think extra locks and fastenings are necessary. "They'll get in any way." Most thieves are always looking for easy jobs. They are soon discouraged by houses they can't get into quickly and easily. So it's worth taking care. This booklet will help you. It's based on the practical experience of police forces throughout the country. Most of the suggestions will cost you only a few minutes extra time and thought. A few may involve some expense, but this is small compared with the loss and unhappiness you might otherwise suffer. If you are in doubt, ask for free advice from the Crime Prevention Officer at your local police station.
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单选题______ the English examination I would have gone to the concert last Sunday. A.In spite of B.But for C.Because of D.As for
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单选题The world has never been more closely and intricately connected. Our behavior (51) the environment we all share, and we are tied into a global economy and global communication system. (52) choosing to buy one garment rather than another we help determine whether someone on the other side of the world retains or (53) their job; emissions from one part of the world contribute to a hole in the ozone layer somewhere else; we can (54) with others anywhere via satellites, the Internet and the mobile phone. This interdependency, (55) "connexity", is the defining characteristic of the world today. However, despite connexity, human beings have also (56) been, more separate. Belief in individual rights and freedoms is at the heart of the West's world view. People nowadays insist their freedom to (57) how to live, who to love, what to consume and what to believe. In economics, the sovereignty of the consumer and the shareholder is paramount. In politics, the sovereignty of nations remains a (58) concern. In this inspiring and important book Mulgan argues that our freedom and our connectedness are set or collision course and argues that the (59) way out of our current impasse (僵局) is to go beyond our sense of ourselves as (60) unit, and recognize the webs of mutual responsibility in which we live.
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