since before的用法想知道这两个单词怎么用有什么区别．只要句型即可．谢谢
问题描述：
since before的用法
想知道这两个单词怎么用有什么区别．只要句型即可．谢谢
答
since+时间点，表示从那个时候起
e.g I have been here since 2000.
before 表示多久以前
e.g We arrived there before it atarted to rain.
答
He has been taught us since 1988.
He taught us before 1989.
答
Since有以下几种用法：当介词用,意思为“自从”如：He has lived here since 1949.自从1949年以来他一直住在这儿.Since seeing you I have had good news.自从遇到你以后我就得到了好消息.当副词用,表示“后来,从那...