The boy was seen ___on the playground.A.play B.to play C.played D.to playing.
问题描述：
The boy was seen ___on the playground.A.play B.to play C.played D.to playing.
答
选A,因为seen是see的过去分词,而see sb. do sth是一个句型,意思是“看见某人做某事（表示看见某人做某事的全过程）”,同时see sb. doing sth.也是一个句型,意思也是“看见某人做某事”,表示的是看见某人做某事的那一瞬间的动作,但以上选项没有playing可以选,所以只能选A.