―Theaccidentmightnothavehappened,hadwebeenmorecareful....

問題詳情：

 ―The accident might not have happened, had we been more careful.     

 ―But we ______.

        A. weren’t                  B. didn’t                       C. hadn’t                      D. don’t

【回答】

A

知識點：虛擬語氣與情態動詞

題型：選擇題