VOA标准英语2016.06.10
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Studying mechanical principles, da Vinci designed many useful devices, such as this machinefor twisting ropes or a crane used to build canals, that greatly improved the efficiency ofRenaissance craftsmen.
达芬奇通过研究机械原理，设计出如用来捻绳的机器或挖掘沟渠的起重机等许多非常有用的设备，极大地提升了文艺复兴时期工匠的工作效率。
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