核心问题
Our friends' plane landed but they weren't on it. They ____ the plane. A. can have missed B. may have missed C. can have lost D. may have lost 我知道答案是 B。但是我不明白为什么不可以选 A。can have done 不是也可以表示推测吗？
词典解答
can have done 虽可对过去事件的可能性表示推测,但是它只能用在否定句和疑问句中。因此,它不能用在上面的肯定句中,见 can 。