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单选题Generation X
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单选题
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单选题Even just a degree or two of greenhouse warming will have a dramatic impact on water resources across western North America. Teams who have modeled the climate in the area are warning of greatly reduced snow packs and more intense flooding as temperatures inch up during the 21st century. It's the first time that global climate modelers have worked so closely with teams running detailed regional models of snowfall, rain and stream flows to predict exactly what warming will do to the area. The researchers, from the National Center for Atmospheric Research in Boulder, Colorado, and elsewhere, were surprised by the size of the effect generated by only a small rise in temperature. Assuming business as usual emissions, greenhouse gases will warm the west coast of North America by just one or two degrees Celsius over the next century, and average precipitation won't change much. But in the model, warmer winters raised the snowline, drastically reducing the crucial mountain snow pack, the researchers told the American Geophysical Union in San Francisco. "We realized that huge areas of the snow pack in the Sierra went down to 15 percent of today's values," says Michael Dettinger, a research hydrologist at the Scripps Institution of Oceanography in La Jolla, California. That caught everyone's attention. The researchers also predict that by the middle of the century, melting snow will cause streams to reach their annual peak flow up to a month earlier. And with warm rains melting snow or drenching already saturated ground, the risk of extreme floods will rise dramatically. We have to believe in these very warm, very wet storms, says Andrew Wood, a water resources modeler at the University of Washington, Seattle. "Since dams can't be filled until the risk of flooding is past, the models predict they will trap just 70 to 85 percent as much run-off as they do now. This is a particular problem for California, where agriculture, industry, a burgeoning population and environmental needs already clash over limited water supplies. We are taking this extremely seriously, " says Jonas Minton, deputy director of the California Department of Water Resources. And observations certainly back up the models. Minton points out that an increasing percentage of California's precipitation over recent decades is falling as rain rather than snow. And Iris Stewart, a climate researcher at the University of California, San Diego, has found that in the last 50 years, run-off peaks in the western US and Canada have been happening earlier and earlier. The cause seems to be a region-wide trend towards warmer winters and springs. Dettinger has little doubt that the models point to a real and immediate problem. "It's upon us, " he says, "and it's not clear what the fix is. /
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单选题Rather like a spoilt child, he can force you into feeling that his survival depends on your ______ presence and care.
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单选题Real innovation is a dying art. It's true that creativity—the business of thinking up new ideas—is far from dead, but it's getting harder and harder to get new concepts applied in design, manufacturing or business. It costs thousands of pounds to get a new idea into the marketplace, and there is very little support for anything from most companies or government. A lot of people don't want to know. I've always been interested in new ideas: I was trained as an engineer and went to work for an automotive components company, and almost from the first day I was asking why things were done in this way and not that. I thought up my first invention at 19—then I discovered someone else had got there first. I've been inventive all my life. I've got 14 patents to my name. Invention is what happens when you come across a problem, and look for a solution. It could be at work or at home in the garden—like a better way of mowing the lawn, say. But these days creativity is being stifled because there are so many hoops to go through. You have a brilliant idea for a left-handed widget but you still have to ask yourself: Is it new? Has it already been protected? Is there a market for it? Is the investment worth it? Only 4 percent of granted patents reach the market place. Part of the problem is that manufacturing industry and government are obsessed with complex technology like bioengineering. There is no interest in low technology or simple ideas that are equivalent to the invention of the paperclip. Inventors still come up with simple devices, but it's difficult to get anyone interested. But it's also a very British problem. Inventions from Britain are often taken up overseas, because most British companies tend not to look outside their own factory gates. My own personal theory is that it's a legacy of the Empire, when Britain had a captive audience and little competition, so industries didn't need to market their products. Nowadays, companies from other leading economies have to make what the consumer wants in order to ensure their profits, so they are always ready to innovate. And many British manufacturers have never caught up. Plus, British schoolchildren aren't embracing vocational training subjects such as metalwork, woodwork, or design and technology. As a result university engineering departments are closing. Tomorrow's World used to be on the TV, but where is that now? The whole lack of interest in creativity and invention is a symptom of the class system, too—there's a kind of snobbishness in Britain about cleverness and originality. The only inventors you see in the media are people like Sir Clive Sinclair and Trevor Bayliss who come across like mad scientists.
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单选题
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单选题In the coming term she will ______ the advanced class. A. take advantage of B. take account of C. take charge of D. take care of
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单选题The fact that blind people can "see" things using other parts of their bodies (31) their eyes may help us to understand our feeling about color. If they can (32) color differences then perhaps we, too, are affected by color unconsciously. By trial and (33) , manufacturers have discovered that sugar (34) badly in green wrappings, that blue foods, are considered (35) and that cosmetics should never be packaged (36) brown. These discoveries have grown into a whole (37) of color psychology that now (38) application in everything from fashion to interior decoration. Some of our (39) are clearly psychological. (40) blue is the color of the night sky and therefore (41) passivity and calmness, while yellow is a day color with associations of energy and incentive. For primitive man, activity during the day meant hunting and attacking, while he saw red as the color of blood and rage and the heat that came with (42) . And green is relevant to passive defense and self-preservation. (43) have shown that colors, partly because of their psychological associations, also have a direct psychological effect. People (44) to bright red show a(n) (45) in heartbeat, and blood pressure; red is exciting. Similar access to pure blue has exactly the opposite effect; it is a (46) color. Because of its exciting of connotations, red was chosen as the (47) for danger, but closer (48) shows that a vivid yellow can produce a more basic state of alertness and alarm, so fire engines and ambulances in some advanced communities are now (49) around in bright yellow colors that (50) the traffic dead.
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单选题Which of the following can NOT be seen inside the aquarium?
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单选题Such euphemisms may be stylistically "permissible" if they are kept within ______. A. boundaries B. ranges C. borders D. limits
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单选题The man who ______ taxes in the area was charged with bribery by the police.A. receivedB. collectedC. gatheredD. accumulated
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单选题A lot of farming techniques have been abandoned because they were too labor ______. A. intense B. intensive C. intensified D. intensifying
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单选题Where did Mr. McCourt come from?
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单选题 In this section, you will hear several passages. Listen to the passages carefully and then answer the questions that follow. Questions 11 to 13 are based on the following passage. At the end of the passage, you will be given 15 seconds to answer the questions. Now listen to the passage.
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单选题The sentence that expresses REQUEST is
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单选题Cars account for half the oil consumed in the U. S. , about half the urban pollution and one fourth the greenhouse gases. They take a similar toll of resources in other industrial nations and in the cities of the developing world. As vehicle use continues to increase in the coming decade, the U.S. and other countries will have to deal with these issues or else face unacceptable economic, health-related and political costs. It is unlikely that oil prices will remain at their current low level or that other nations will accept a large and growing U.S. contribution to global climatic change. Policymakers and industry have four options: reduce vehicle use, increase the efficiency and reduce the emissions of conventional gasoline-powered vehicles, switch to less harmful fuels, or find less polluting driving systems. The last of these--in particular the introduction of vehicles powered by electricity-is ultimately the only sustainable option. The other alternatives are attractive in theory but in practice are either impractical or offer only marginal improvements. For example, reduced vehicle use could solve traffic problems and a host of social and environmental problems, but evidence from around the world suggests that it is very difficult to make people give up their cars to any significant extent. In the U. S. , mass-transit ridership and carpooling have declined since World War Ⅱ. Even in Western Europe, with fuel prices averaging more than $ 1 a liter (about $ 4 a gallon) and with easily accessible mass transit and dense populations, cars still account for 80percent of all passenger travel. Improved energy efficiency is also appealing, but automotive fuel economy has barely made any progress in 10 years. Alternative fuels such as natural gas, burned in internal-combustion engines, could be introduced at relatively low cost, but they would lead to only marginal reductions in pollution and greenhouse emissions (especially because oil companies are already spending billions of dollars every year to develop less polluting types of gasoline).
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单选题TheUSmilitarysaysthejointmilitaryactionisaimedto_______.
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单选题The judger doesn't know whether the witness is telling the truth, but he will ______ it.A. identifyB. enforceC. distinguishD. verify
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单选题Executives of the company enjoyed an ______ lifestyle of free gifts, fine wines and high salaries.A. exquisiteB. extravagantC. exoticD. eccentric
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单选题In this section, you will hear several news items. Listen to them carefully and then answer the questions that follow. Question 21 to 22 are based on the follwing news. At the end of the news item, you will be given 10 seconds to answer the questions. Now, listen to the news.
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