分析句子结构To save some of the human language before they are forgotten

问题描述:

分析句子结构To save some of the human language before they are forgotten
To save some of the human languages before they are forgotten,the students in our school started
a discussion "Save Our voice“.
请问To save some of the human languages before they are forgotten这个目的状语从句中before they are forgotten作什么成分?修饰什么?

To save some of the human languages是不定式作目的状语
不定式属于非谓语,非谓语具有动词的特征,所以要修饰动词的话
就要状语来修饰,before they .在.之前,时间状语修饰不定式