精选优质文档-倾情为你奉上现在完成时中“since”和“for”的区别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+ agoI 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.Since 用来说明动作起始时间，for用来说明动作延续时间长度。I have lived here for more than twenty years.I have lived h
