什么是定语从句？如何区分？

用来修饰主语的那个成分就是定语从句啦。其实那个很简单的，关键是要把先行词找到。
比如，The tree that grows in front of my house is dying.先行词是哪部分？看出了它的修饰部分了吗？那部分就属于定语从句。
再给你两个例子。
1.This the ruler that I bought for you.
2.I want to introduce a man who is very preaty to you.
没找出来的话，就问。

这是什么问题？