He looked as if he ­­­ the answer.A. knewB. had knownC. knows D. has known

网友回答

A. knew
(答案→)B. had known
C. knows
D. has known
解析：本题考查as if后接从句使用虚拟语气的用法。如果as if后面的从句表示与过去的事实相反使用过去完成时;as if后面的从句表示与现在或者将来的事实相反，句子中用过去时。本句是与过去事实相反，所以选择B。