定语从句怎样判断关系代词是做主语还是宾语He is the man.He came here last week.He is the man who came here last week She is the woman.I served her yesterday.She is the woman I served yesterday.They are the books.I bought the books last year.They are the books I bought last year这里的关系代词who是做主语还是宾语是怎样判断的,求解
问题描述：
定语从句怎样判断关系代词是做主语还是宾语
He is the man.
He came here last week.
He is the man who came here last week
She is the woman.
I served her yesterday.
She is the woman I served yesterday.
They are the books.
I bought the books last year.
They are the books I bought last year
这里的关系代词who是做主语还是宾语是怎样判断的,求解
答