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在美国东北部和中部。近20亿亩面积的森林曾被砍毁垦荒,1934年发生了一场举世闻名的[黑风暴],刮了三天三夜,越过了美国三分之二的大陆,把足以装满
In the northeastern and central United States. Nearly 2 billion acres of forest area had been cut down and reclaimed land. In 1934 there was a world-famous [Black Storm]. It took three days and three nights and crossed the two-thirds of the U.S. mainland continent,