阅读理解

　　We often think of the future．We often wonder what the world will be like in a hundred years' time．

　　In the area of space travel, perhaps a permanent(永久性的)station on the moon will have been set up．Perhaps people will be able to visit the moon as tourists．Cheap rockets for space travel will have been developed, permitting(容许)long journeys throughout the solar system(太阳系)．When that day comes, people will be taking vacations in space and visiting other planets．

　　Great progress will have been made in medicine, too．Perhaps a cure(对策)will have been discovered for cancer(癌症)．Pollution is a problem we must solve．In a hundred years' time it will have been controlled．

　　All the world will have been developed－even Antarctica．There will be large cities in Antarctica．We already have supersonic(超音速的)flight, but in a hundred years' time, we will have super-sonic land travel as well．

　　We will have used up most of the earth's land to build our cities, so floating(飘浮的)cities will have been built．The Japanese already have plans for cities of this kind．And there will be cities under the sea．The first of these will have been completed．

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