.We were all waiting for you .You for the seaside by yourself without leaving a message.
A. mustn’t leave
B. shouldn’t have left
C. couldn’t have left
D. needn’t leave
网友回答
A. mustn’t leave
(答案→)B. shouldn’t have left
C. couldn’t have left
D. needn’t leave
解析:这是情态动词的特殊用法,shouldn’t have left表示本来不应该做但实际已经做了。