【www.tuzhexing.com--小学】
这篇关于小学英语语法小升初必备：since的四种用法，是人才资讯网特地为大家整理，希望对大家有所帮助！
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.