【判断题】
用钳表测量电动机空转电流时,可直接用小电流档一次测量出来
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在下面对OSI参考模型的数据链路层的功能特性描述中，哪一项是不正确的？___
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He has made it very clear ___ we should observe the new rules.
A. what
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A. that
B. then
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A. returned
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___ they have written about the behaviors of animals is hardly anything new.
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