– He promised to come to see you.
问题描述：
– He promised to come to see you.
- But he _______ .I've been alone.
A doesn't B didn't C won't D hasn't
这里答案是选D 我想问 B D与B有什么区别?
答
这里区别完成时 和过去时的区别.
完成时有表示从过去到现在 并对现在形成影响 而过去时并没有强调对现在的影响
因此 我至今仍然一个人 就是他没有来的对现在的影响 那么应该用完成时.