The Bunsen Burner is so named because it is thought by Robert Bunsen. A. to be i

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

试题答案

D

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。