they were playing on the computer__their teacher came in.A.when B.until C.while D.after
they were playing on the computer__their teacher came in.A.when B.until C.while D.after
这道题选A,请问为什么不能选until或者after,如果能系统讲解更好
这道题选A,请问为什么不能选until或者after,如果能系统讲解更好
英语人气：395 ℃时间：2019-10-17 07:46:48
优质解答
until 是直到的意思,after是之后,你要注意前面用的是过去进行时,正在玩电脑,强调的是在某一时刻正在做某事,选项中只有when符合.是不是until和after前后时态都是要统一用过去式而不能是进行时呢？我不敢说都是。因为我不学英语很久了，现在只剩老底子，我不确定不敢瞎说，具体问题具体分析吧，你有问题还可以问我，应该可以帮到你。
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