He seemed to me at the party last month but I can’t remember well now ．A. to introduce B.

问题补充：

He seemed to me at the party last month, but I can’t remember well now ．

A. to introduce

B. to have introduced

C. to be introduced

D. to have been introduced

答案：

A. to introduce

B. to have introduced

C. to be introduced

(答案→)D. to have been introduced

解析：考查seem to have done似乎已经做了什么，he和introduce是被动关系，用不定式的完成被动式，句意：上个月的聚会上好像有人把他介绍给我了，但我现在记不清了。选D.