手持式电动工具使用前必须检查（）完好无损后，才能通电运行。

三相四线制中性线的作用主要是（）。 点击查看答案

听力原文：It's a bit chilly outside, don't you think?(A) Yes, I guess it'll soon be winter.(B) I am not sure whether he will like this chilli sauce.(C) Yes, that chilli dog was really spicy.(10)A． B． C．

A.
(B)
B.
(C)
C.
(10)
A．

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