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来源:雅诚德英语网
Water was the main source of mechanical power, and by the end of the seventeenth century, England alone is thought to have had some 20,000 working mills.
水是机械动力的主要来源,而到了17世纪末,人们认为仅英格兰就有2万个左右的工作磨坊。
Water was the main source of mechanical power, and by the end of the seventeenth century, England alone is thought to have had some 20,000 working mills.
水是机械动力的主要来源,而到了17世纪末,人们认为仅英格兰就有2万个左右的工作磨坊。