How _________ this word pronounced?
A. was
B. has been
C. is
D. had been
查看答案
It is impossible for lost money _________ by ourselves.
A. to be found
B. be found
C. to being found
D. being found
机器的主要作用是利用机械能做功或实现能量的转换
A. 对
B. 错
机构的主要功用在于传递或转变运动的形式。
A. 对
B. 错
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