高校问答飞儿乐团演出服:since用法
来源：百度文库 编辑：高校问答 时间：2024/05/10 07:52:54
since的四种用法
1) since +过去一个时间点 (如具体的年、月、日期、钟点、1980, last month, half past six)。
I have been here since 1989.
2) since +一段时间+ ago
I have been here since five months ago.
3) since +从句
Great changes have taken place since you left.
Considerable time has elapsed since we have been here.
4) It is +一段时间+ since从句
It is two years since I became a postgraduate student.
http://www.hongen.com/eng/pub/yufac/1113.htm