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

题目

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?

答案

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