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小知识法国人德·西弗拉克在1690年曾做过一辆两轮车,使用方法是:两腿分开坐在车上,两脚蹬地使之滚动向前。1839年,麦克米伦发明了一种机械
Little knowledge Frenchman De Siflak had made a two-wheeled vehicle in 1690. The method was to use two legs apart and sit in the car, rolling it forward with both feet. In 1839, Macmillan invented a machine