The book, that I borrowed from the library, is very interesting.

The book, whose I borrowed from the library, is very interesting.

The book, which I borrowed from the library, is very interesting.

The book, who I borrowed from the library, is very interesting.

It is in the place where we first met.

This is the place and we first met.

This is the place which we first met.

It is at this place that we first met.

定语从句

状语从句

名词性从句

并列句

who

whom

which

where

when