.— John,you _____ go out to play until your homework __________ .—OK,Mum..Amust; finishes B.can’t; is finished C.can’t; has finished D.needn’t; finishes
问题描述：
.— John,you _____ go out to play until your homework __________ .—OK,Mum.
.Amust; finishes B.can’t; is finished C.can’t; has finished D.needn’t; finishes
答
C 约翰，你不能去外面玩直到作业完成
答
C
not until 直到……才……
因为是完成作业，所以用现在完成时态，has/have＋动词的过去式
John.直到你完成作业才能去玩
答
选 B can’t; is finished homework,是被做完的,所以一定要用被动语态.这里只有 B 里的 is finished 是被动语态.C has finished 是现在完成时,不行.如果要用现在完成时,要说：until your homework has been finished...
答
排除a,d.选c.
应注意until的用法。
until和现在完成时有关。
until前是否定形式。