机构和机器的区别是，机构只能实现运动的传递或者运动形式的转换，而机器可以变换和传递能量。
查看答案
所有内燃发动机的凸轮轴，都是通用零件。
A. 对
B. 错
一般我们见到的圆柱销钉，它属于通用零件。
A. 对
B. 错
---Excuse me,is the museum far from here? ----No,it’s about ________ .
A.5 minutes walk
B. 5 minute walk
C. 5 minutes’ walk
D. 5 minute’s walk
—What brought joy to Linda just now? —________. ?
A. Received a gift
B. She received a gift
C. Receiving a gift
D. Because she received a gift
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