The flu is believed by viruses that like to reproduce in the cells inside the hu
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The flu is believed______by viruses that like to reproduce in the cells inside the human nose and throat.
A.causing B.being caused
C.to be caused D.to have caused
试题答案
C
解析:
本题考查的是非谓语动词。be believed to do 为习惯性搭配。the flu 与cause 为动宾关系，所以用被动语态。