If headaches only occur at night, lack of fresh air is often the cause.

A．start

B．begin

C．happen

D．visit

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参考答案

【题干】如果头疼只发生在晚上，原因经常就是缺乏新鲜空气。
A ．开始 B ．开始 C ．发生 D ．拜访
【解析】本题考查动词。划线单词 occur 的意思是“发生”，与 happen 意思相同，故选 C 。

1 The ice is not thick enough to bear the weight of a tank.

A．suffer

B．accept

C．receive

D．support

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2 A small number of firms have ceased trading.

A．completed

B．finished

C．fulfilled

D．stopped

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3 She was sent a box of chocolates along with a letter saying she was fired .

A．killed

B．shot

C．dismissed

D．murdered

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