years ago与before two years的区别.

问题描述:

years ago与before two years的区别.

two years ago用在句首
before two years用在句末

two years ago用在一般现在时 before two years用在过去时,懂了吗?

ago前加时间段,before加时间点
eg; two years ago
before three o'clock

two years ago比较常用,至于before two years好像英语中不那么说

ago表示“从现在起的若干时间以前”,意思是“距今……以前”,需和过去时或过去进行时连用.
before泛指“从过去起的若干时间以前”,意思是“距过去某时……以前”“与其……(毋宁)”,常和完成时连用.