By the time Jack returned home from England, his son. from college.A．gradua

题型：不详难度：来源：

By the time Jack r

eturned home from England, his son. from college.

A．graduated	B．has graduated
C．had been	D．had graduated

答案

解析

考查动词时态，By the time 截止到过去某时间为止做了某事，用过去完成时态。 A是一般过去时；B是现在完成时；C是过去完成进行时。根据句子意思“截止到Jack从英国返家，他的儿子已经大学毕业了。

举一反三

Last month, the Japanese government expressed their thanks for the air they_______ from China.

A．receive

B．are receiving

C．have received

D．had received

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—Pity you missed the lecture on nuclear pollution

.
—I____ it, but I was busy preparing for a job interview.

A．attended	B．had attended
C．would attend	D．would have attended

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Experience of this kind in both the U.S. and Europe well before the Second World War.

A．have conducted	B．have been conducted
C．had conducted	D．had been conducted

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Tom in the library every night over the last three months.

A．works

B．worked

C．have been working

D．had been working

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—That must have been a long trip.
—Yeah, it us a whole week to get there.

A．takes

B．has taken

C．took

D．was taking

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