The research is so designed that once _____ nothing can be done to change it.A．

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The research is so designed that once _____ nothing can be done to change it.

A．begins

B．having begun

C．beginning

D．begun

答案

解析

可视为once it is begun之省略。

举一反三

Each of the students, hoping to pass the exam, _____the book.

A．buying

B．having bought

C．should buy

D．to buy

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Many countries, for example, Mexico and Japan, _____a lot of earthquakes.

A．have

B．having

C．to have

D．having had

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The scientist has made quite a few discoveries, ______ of great importance to the whole world.

A．which I think they are	B．which I think are
C．I think which are	D．that I think they are

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It is in Steven Spielberg" s first film, Jaws, ____ a big white shark attacks swimmers ____ are spending their holidays in a small village by the sea.

A．where; who

B．which; that

C．that; that

D．where; that

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The reason Beethoven went away to the country is ______.

A．that he was gradually going deaf

B．because he was gradually going deaf

C．on account of the fact that he was gradually going deaf

D．since he was gradually going deaf

题型：不详难度：| 查看答案