People living on parts of the south coast of England face a serious problem. In 1933, the owners of a large hotel and of several houses discovered, to their surprise that their gardens had disappeared overnight. The sea had eaten into the soft limestone cliff (悬崖) on which they had been built. While experts were studying the problem, the hotel and several houses disappeared altogether, sliding down the cliff and into the sea. Erosion (侵蚀) of the white cliffs along the south coast of England has always been a problem but it has become more serious in recent years. Dozens of homes have had to be abandoned as the sea has crept farther and farther inland. Experts have studied the areas most affected and have drawn up a map for local people, forecasting the year in which their homes will be eaten up by the hungry sea. Angry owners have called on the Government to erect sea defenses to protect their homes. Government surveyors have pointed out that in most cases, this is impossible. New sea walls would cost hundreds of millions of pounds and would merely make the waves and currents further along the coast, shifting the problem from one area to another. The danger is likely to continue, they say, until the waves reach an inland area of hard rock, which will not be eaten as limestone is. Meanwhile, if you want to buy a cheap house with an uncertain future, apply to a house agent in one of the threatened areas on the south coast of England. You can get a house for a knockdown price but it may turn out to be a knockdown home. 小题1: What is the cause of the problem that people living on parts of the south coast of England face?
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A、Porque los chinos suelen pedir ayuda a sus familiares cuando se encuentran en una situación difícil.
B、Porque la familia es uno de los factores más importantes para lograr la felicidad.
C、Porque los chinos creen que los familiares son los más honrados.
D、
Every geologist is familiar with the erosion cycle. No sooner has an area of land been raised alive sea-level than it becomes subject to the erosive forces of nature. The rain beats down on the ground and washed【51】the finer particles, sweeping them into rivulets and then into rivers and out to sea. The frost freezes the rain water in cracks of the rocks and breaks【52】even the hardest of the constituents of the earth's crust. Blocks of rock dislodged at high levels are brought down by the force of gravity. Alternate heating and【53】of bare rock surfaces causes their disintegration. In the dry regions of the world the wind is a powerful force in removing material from one area to another. All this is natural. But nature has also provided certain defensive forces. Bare rock surfaces are in【54】course protected by soil itself dependent initially on the weathering of the rocks. Slowly【55】surely, different types of soil with differing "profiles" evolve the main types depending primarily on the climate. The protective soil covering, once it is formed, is held together by the growth of vegetation. Grass and herbaceous plants,【56】long, branching tenuous roots, hold firmly together the surface particles. The【57】is true with the forest cover. The heaviest tropical down- pours beating on the leave of the giant trees reach the ground only【58】spray, gently watering the surface layers and penetrating along the long passages provided by the roots to the lower levels of the soil. The soil, thus protected by grass, herb, or trees, furnishes a quiet habitat for a myriad varied organisms-earth-worms that importantly modify the soil, bacteria, active in their work of converting【59】leaves and decaying vegetation into humus and food for the growing plants. Chemical action is constantly taking【60】. Soil acids attack mineral particles and salts in solution move from one layer in the soil to another.
(51)
A) Stronger at high temperatures than at low temperature.
B) Easy oxidation at high temperature
C) High specific strength
D) Good resistance to thermal shock.
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