一道英语选择题

题目

一道英语选择题
-David promised to come round to have supper with us today.
-But he_____.I've been alone for half an hour.
A.won't
B.hadn't
C.hasn't
D.doesn't
正确答案好象是A,但为什么BD不可以?

答案

-David promised to come round to have supper with us today.
-But he_____.I've been alone for half an hour.
A.won't B.hadn't C.hasn't D.doesn't
正确答案好象是A,但为什么BD不可以?
答：C
译：戴维答应过今天过来和我们一起吃晚饭.
可他还没有来.我一个人（都等了）半个小时了.
析：此回答为省略句.如不省略,则为：But he hasn't come yet.可他到现在都还没有来.
B.是过去完成是,相对于过去某个时间之前发生的事或存在的情况,显然不妥.A=he won't come.表示他不愿意来,与前句矛盾.D是一般现在时,表示经常发生的情况.