than before ,before 是副词么?

问题描述:

than before ,before 是副词么?
He is richer than before
than before 结构非常常见.请问 这里的 before 是 介词,副词,还是连词?因为 before有三种词性.呵呵.than 这里算是 介词,还是连词?
之前有看到 有人写 He is richer than before = He is richer than he was before
说 before 做表语了?
大致说说,如果有省略的句子或其他用法.也说说.
than 是副词的话,副词后面能跟 before

一、He is richer than before 是 He is richer than he was rich before 的省略.句中的 than 是连词,后面引导的是一个省略了与上文重复的主谓部分 he was rich,before 是副词,充当比较状语从句中的时间状语.二、判...