Question

The man we followed suddenly stopped and looked as if          whether he was going in the right direction

1. A.
   seeing
2. B.
   having seen　
3. C.
   to see
4. D.
   to have seen

Answer 1

C
解析：
as if to see="as" if he were(was) to see，as if引導的表語從句或者方式狀語從句可以采用這種省略形式。