My cell-phone has disappeared. Who have taken it away?
A. could
B. should
C. must
D. might
网友回答
(答案→)A. could
B. should
C. must
D. might
解析：考查情态动词。句意：我的cellphone不见了，会是谁把它拿走了呢?此处could have done表示“可能做过某事”。should have done表示“本来应该做某事(但实际上并没有做)”；must have done表示“一定做了某事”；might have done表示“也许做了某事”。