风的作用(1)
夏日的风可以带来凉意，冬日的风可以吹起漫天的雪花，此外，风还有什么作用呢？http://t1.g.hjfile.cn/voasp/rm/2007/03/20070302.mp3For centuries, farmers have used windmills to pump water, crush grain and perform other tasks. Today, farmers can earn money with high-powered wind turbines that produce electricity. Wind power has become big business, especially in Europe.In the United States, less than one percent of electricity…
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