题目内容

The rain fell so heavily that water () through the ceiling.

A.faded
B.leaked
C.leaped
D.fell

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用兆欧表测量绝缘电阻前要先切断被测设备的电源,并将设备的导电部分与大地接通,进行充分放电,以保证安全。

当主驱动链被过度拉伸或断裂,主驱动链保护装置能使自动扶梯(自动人行道)停止运行。

Can the best student become ()?

A.as best as ever
B.as good as ever
C.better than ever
D.the best as ever

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