He was seen a letter in his bed room.A. writeB. to writeC. writtenD. wrote

问题补充：

He was seen a letter in his bed room.

A. write

B. to write

C. written

D. wrote

答案：

A. write

(答案→)B. to write

C. written

D. wrote

解析：感观动词see，后跟不带to的不定式see sb/sth do，被动形式需要加to，句意：他被看见在他的卧室写了一封信。所以选B。