题目内容

The Bunsen Burner is so named because it is thought ___________ by Robert Bunsen.

A. to be invented               B. having been invented

C. invented                     D. to have been invented

D


解析:

本句考查动词的被动语态和时态,it+is+动词ed形式,to do是固定的搭配用法。而Bunsen Burner的发明是过去发生的动作,所以用完成时态。

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