2014年英语六级阅读练习及答案(25)_大学英语阅读

2014年英语六级阅读练习及答案(25)

　　This increased demand for food will create an increased demand for water. Certain parts of the United StatesNevada, New Mexico, and Arizona, for examplehave been in desperate need of water for a long time. Periodically, the citizens of New York have been water-rationed because droughts have seriously threatened the water supply in the reservoirs which provide the millions of gallons a day needed in the largest city in the world.

　　Scientists will solve the water problems of the desert and metropolitan areas. Rain-makers will have perfected a simple method, now in the elementary stages of experimentation, for making clouds release their moisture so that the right amount of rain is produced to keep reservoirs at the correct level at all times of the year.

　　Another method of water production will be the purification of salt water taken from oceans. When a simple, cheap method has been worked out for converting seawater into pure water suitable for use in the household and the manufacturing plant, other scientist-engineers will contribute practical mechanical equipment for piping the water from seashore to desert areas.

　　Other improvements of the future will touch our lives more closely. It is possible, for example, to imagine that cities of the future will have underground networks of conveyor belts which would supplement subways and make it possible for people to hop on a rapid conveyor system, sit in a little booth, and shuttle a couple of blocks in safety.