问题
选择题
My sister met him at the Grand Theater yesterday afternoon, so he _______ your lecture.
A．couldn’t have attended
B．needn’t have attended
C．mustn’t have attended
D．shouldn’t have attended
答案
答案：A
考察情态动词，couldn’t have attended不可能做了某事 needn’t have attended本不需要干某事
mustn’t have attended禁止干某事 shouldn’t have attended本不应当干某事
句意为，我的姐姐昨天下午在大剧院遇到了他，因此他不可能参加了你的讲座