there be引导的定语从句who做主语能省略who吗

问题描述:

there be引导的定语从句who做主语能省略who吗

There are three students who are cleaning the classroom.
楼主是指这样的句子?
这个who在从句中是做主语的,不能省.
但可用分词短语代替定语从句,即:
There are three students cleaning the classroom.