He won the scholarship. He ______ hard these terms.A.should have workedB.must have workedC

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He won the scholarship. He ______ hard these terms.

A.should have worked

B.must have worked

C.must have been working

D.could have worked

热搜:关于氨基酸代谢错误的论述是_________。

答案解析

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  • 正确答案:C
    解析:本题考查的是情态动词表示推测的情况。must表示肯定推测,接现在时表示对现在的肯定推测;接完成时则表示对过去情况的肯定推测。同样,接现在完成进行时,则表示对一直以来情况的推测。根据题意,是说他这些学期以来一定一直都很努力学习,所以选C。