――Wedidnotseehimatthelectureyesterday. ――You

問題詳情：

―― We did not see him at the lecture yesterday. 

―― You _____ him, since I went to an international conference with him.

A. mustn’t have seen                                  B. can’t have seen

C. couldn’t see                                          D. needn’t have seen

【回答】

知識點：虛擬語氣與情態動詞

題型：選擇題