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Usually alternating current (AC) transmission suffers lower losses than direct current (DC), and thus, AC became the industry standard. Some people, however, question that standard because over long distances high-voltage DC lines suffer lower losses than AC. Not only does that make them better in their own right, but employing them would allow electricity grids to be restructured in ways that would make wind power more attractive. That would reduce the need for new conventional (and polluting) power stations.Wind power has some problems. You don’t always get it where you want it and you don’t always get it when you want it. The question of where the wind is blowing would no longer matter because it is almost always blowing somewhere. If it were windy in Spain but not in Ireland, current would flow in one direction. Dealing with when the wind blows is a subtler issue. For instance, an important part of Dr Schmid’s continental grid is the branch to Norway. It is not that Norway is a huge consumer. Rather, the country is well supplied with hydroelectric plants. These are one of the few ways that energy from transient sources like the wind can be stored in grid-filling quantities. The power is used to pump water up into the reservoirs that feed the hydroelectric turbines. That way it is on tap when needed. The capacity of “Norway’s reservoirs is so large, according to Dr Schmid, that should the wind drop all over Europe—which does happen on rare occasions—the hydro plants could spring into action and fill in the gap for up to four weeks.Put like this, a Europe-wide grid seems an obvious idea. That it has not yet been built is because AC power lines would lose too much power over such large distances. Hence the renewed interest in DC. Dr Schmid calculates that a DC grid of the sort he envisages would allow wind to supply at least 30% of the power needed in Europe. Moreover, it could do so reliably—and that means wind power could be used for what is known in the jargon as base-load power supply.Though wind power has its opponents, too, its environmental virtues might be enough to swing things in its favor if it were also reliable. Indeed, a group of Norwegian companies have already started building high-voltage DC lines between Scandinavia, the Netherlands and Germany, though these are intended as much to sell the country’s power as to accumulate other people’s. And Airtricity—an Irish wind-power company—plans even more of them. It proposes what it calls a Supergrid. This would link offshore wind farms in the Atlantic Ocean and the Irish, North and Baltic seas with customers throughout northern Europe.51. By saying “make them better in their own right” (Paragraph 1), the author means ______.52. By “current would flow in one direction” (Paragraph 2), the author is actually referring to ______.53. How will consumers think of a DC electricity grid?54. Why does Dr Schmid’s continental grid locate in Norway?55. Which of the following is TRUE according to the passage?



A.realize the right of DC B.make DC suffer lower losses C.make DC more useful than AC D.make better use of DC to transfer power
问题2:
A.current flows from Spain to Ireland B.current flows from Ireland to Spain C.current flows from Ireland to other places D.current flows from Spain to other places
问题3:
A.Useless B.Feasible C.Troublesome D.Comfortable
问题4:
A.To make use of the country’s capacity of reservoirs. B.To make use of the country’s rich wind power. C.It is simply Dr Schmid’s personal preference. D.Because traditional power plants in Norway cannot meet consumers’ demand.
问题5:
A.Wind power has won universal support. B.Companies hesitate to invest in wind power. C.The prospect of wind power so far seems very positive. D.Wind farms on oceans can supply power demand of the whole Europe in the future.

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Do you remember last summer, when furious travelers were pounding on Congress to do something about airline customer service? Airlines promised to improve, and they adopted new standards just before Christmas. But as another summer nears, plenty of experienced travelers don’t see much improvement in customer service overall.This month, the Department of Transportation’s (DOT) inspector general’s office will issue its first critical article on whether airlines are honoring their promises. One survey suggests problems: The number of complaints to the DOT about the top 10 airlines in the first quarter soared 89% from a year ago.Hit last summer by passenger complaints and the threat of consumer-protection laws by Congress, 14 carriers voluntarily agreed to adopt a set of basic customer-service standards called Customers First. From immediate refunds to truthful reservation agents to toilets that flush during onboard delays, the “12 commitments” to passengers were introduced as a major effort to improve service. Since then, airlines have been redesigning websites, retraining employees and upgrading technology. Recently, DOT inspector general Kenneth Mead, at McCain’s request, sent 20 examiners to airports to document whether each airline is doing what it promised. Mead cautions travelers shouldn’t expect too much. Most of the promises are aimed at better communication with customers, not problems free flights.“We think passengers, both business and leisure, perceive travel as more of a quarrel these days,” spokeswoman Shelly Sasson says. “Some of this is perception, but a lot is reality.” “And when improvements are made, it takes a long time for them to be noticed”, she says. Now, the efforts may be working. During the first quarter, Delta had the second-lowest rate of complaints among the top 10carriers. Still, its rate, along with other carriers, is up from last year. McCain and other lawmakers say new consumer protection laws aren’t out of the question if the industry’s voluntary program doesn’t work.56. The passage tells us that ______.57. Which of the following is NOT mentioned in the passage?58. Which of the following statements is closest in meaning to the sentence “Some of this is perception, but a lot is reality.” (Para. 5)?59. The author has written the last paragraph mainly to mean ______.60. In paragraph 1, the phrase “pounding on” means “______”.



A.passenger complaints increase though airlines have taken steps to improve air service B.passenger complaints decrease for airlines have taken steps to improve air service C.air service has been improved greatly though it is hard to be noticed by passengers D.air service needs improving badly as the results of passenger complaints
问题2:
A.Government has sent officials to check any improvement the air service airlines have made. B.Some people suggest passengers show more understanding to airlines about their efforts to better air service. C.To improve air service doesn’t mean that there will no longer be any deficiencies in air traveling. D.It is thought that passengers should be patient when they are waiting for any improvement made by airlines.
问题3:
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