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Scientists have many theories about how the universe ___ into being.

A. came                                     B. was coming

C. had come                               D. would come

A


解析:

考查時(shí)態(tài)的用法。宇宙是如何形成的,因?yàn)橛钪娴男纬蛇@個(gè)動(dòng)作已經(jīng)發(fā)生,所以用一般過(guò)去時(shí)來(lái)表示已經(jīng)發(fā)生的動(dòng)作。

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