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One billion people in the world are short of water. How can this problem be solved Some suggestions have been to desalinate ocean water or to build enormous water pipelines from areas where water is abundant. (Suggestions such as these prove extremely expensive when they are actually used. ) One possibility that scientists are considering is pulling icebergs from either the North Pole or the South Pole to parts of the world with a water shortage. Although many questions must be answered before such a project could be tried, moving icebergs seems a reasonable possibility in the future.Engineers, mathematicians, and glaciologists from a dozen countries have been considering the iceberg as a future source of water. Saudi Arabia is particularly interested in this project because it has a great water shortage. Scientists estimate that it would take 128 days to transport a large iceberg (about 1/2 square mile) to Saudi Arabia. Yet the iceberg would be completely melted by the 104th day. Therefore, insulation would be essential, but how to insulate the iceberg remains an unsolved problem.The problems in transporting an iceberg are numerous. The first problem is choosing the iceberg to pull. The icebergs that form in the North Pole are quite difficult to handle because of their shape. Only a small portion extends above the water — most of the iceberg is below the surface, which would make it difficult to pull. South Pole icebergs, on the other hand, are flat and float like table tops. Thus they would be much easier to move.How can a 200-million-ton iceberg be moved No ship is strong enough to pull such enormous weight through the water. Perhaps several ships could be used. Attaching ropes to an iceberg this size is also an enormous problem. Engineers think that large nails or long metal rods could be driven into the ice. What would happen if the iceberg splits into several pieces during the pulling Even if an iceberg with very few cracks were chosen, how could it be pulled through stormy waters Furthermore, once the iceberg reached its destination, very few ports would be deep enough to store it.All of these problems must be solved before icebergs can become a reasonable source of water. Yet scientists estimate that it will be possible to transport them in the near future. Each year, enough icebergs form to supply the whole world with fresh water for a full year. In addition, icebergs are free and nonpolluting. As a solution to the world’s water problems, icebergs may be a workable possibility. What is the main idea of the passage（）
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At four thousand feet, wide plains begin to appear, and there is never a moment when some distant mountain is not（）
In Japan, most people still feel that a woman’s place is in the home; and most women willingly accept their (31) role as wife, leaving the business of making a living (32) their husbands. For those who do want a (33) of their own, opportunities are limited, and working women usually have to (34) for low wages, fewer promotions, less responsible (35) .In America, on the other hand, most women, (36) wives and mothers, work most of their times. But (37) few have had real careers. As in Japan, most fields are (38) by men and opportunities for women have been (39) , salaries low, chances for advancement (40) American women work mainly because they (41) ; in these days of inflation and luxury living, (42) income per family is simply not enough to (43) . So American women actually have two jobs: one nine-to-five position outside the home, and (44) round-the-clock in the home job (45) wife, housemaid, cook and nurse.One of the main goals of the modern women’s liberation movement, which started (46) , was to eliminate sex discrimination in the work force, and to (47) careers for women that were previously (48) for men. And though there is still a long way to (49) , a lot of progress has been (50) . (42)（）
In Japan, most people still feel that a woman’s place is in the home; and most women willingly accept their (31) role as wife, leaving the business of making a living (32) their husbands. For those who do want a (33) of their own, opportunities are limited, and working women usually have to (34) for low wages, fewer promotions, less responsible (35) .In America, on the other hand, most women, (36) wives and mothers, work most of their times. But (37) few have had real careers. As in Japan, most fields are (38) by men and opportunities for women have been (39) , salaries low, chances for advancement (40) American women work mainly because they (41) ; in these days of inflation and luxury living, (42) income per family is simply not enough to (43) . So American women actually have two jobs: one nine-to-five position outside the home, and (44) round-the-clock in the home job (45) wife, housemaid, cook and nurse.One of the main goals of the modern women’s liberation movement, which started (46) , was to eliminate sex discrimination in the work force, and to (47) careers for women that were previously (48) for men. And though there is still a long way to (49) , a lot of progress has been (50) . （37）（）
In Japan, most people still feel that a woman’s place is in the home; and most women willingly accept their (31) role as wife, leaving the business of making a living (32) their husbands. For those who do want a (33) of their own, opportunities are limited, and working women usually have to (34) for low wages, fewer promotions, less responsible (35) .In America, on the other hand, most women, (36) wives and mothers, work most of their times. But (37) few have had real careers. As in Japan, most fields are (38) by men and opportunities for women have been (39) , salaries low, chances for advancement (40) American women work mainly because they (41) ; in these days of inflation and luxury living, (42) income per family is simply not enough to (43) . So American women actually have two jobs: one nine-to-five position outside the home, and (44) round-the-clock in the home job (45) wife, housemaid, cook and nurse.One of the main goals of the modern women’s liberation movement, which started (46) , was to eliminate sex discrimination in the work force, and to (47) careers for women that were previously (48) for men. And though there is still a long way to (49) , a lot of progress has been (50) . (39) （）
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