where has this letter come from能把has换成is吗?
来源:百度知道 编辑:UC知道 时间:2024/06/22 03:52:14
两者有什么区别?
此处come是come的过去分词,可以把has换成did 或does
语句中用了have done语式,表"过去的过去"
不能,因为这个句子里面已经有个动词come了,同一个句子里面只能有一个动词,所以不能用IS。
不能!如果换成IS,不就有两个动词IS和COME了嘛!
把HAS改为does
可以换成did 或does
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this class has 16 students.
He has c_______in this exam.
This book has three pages____
this trial version has exrired
Where did you go this summer?
This is the house where we lived
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