定语从句中怎样区分关系词是作宾语还是主语?

问题描述:

定语从句中怎样区分关系词是作宾语还是主语?
例如He is the man that lives next door
The girl that we saw yesterday is Jim’sister

He is the man that [lives next door].
主语 that引导的定语从句
The girl that [we saw yesterday]是主语
that引导的定语从句