since可以和过去完成进行时连用吗

since的用法主要有两点：一是表示“自从……以来”,二是表示“既然”之意.但如果只了解词的含义,而不了解其用法,在使用时就会造成错误.例如：I have not heard from him since I lived in Shanghai.不少人会望文生义,将该句译为：“自从我住在上海以来,就再也没有收到他的信了.”而实际上这个句子的译文并非如此,那么正确的含义是什么呢?下面谈谈since作连词引导时间状语从句的用法.一、若since引导的状语从句的谓语动词是终止性的过去时,则从句表示的时间是“从动作开始的那一时刻起”.如：He has studied very hard since he came to our school.自从他来到我们学校,他学习就非常努力.We have been missing them since they left here自从他们离开这里,我们就一直很想念他们.这是最常见的一种用法,此处不再多述.二、若since引导的状语从句的谓语动词是持续性动词或表示状态的动词的过去时时,则从句表示的时间是“从那持续动作或状态结束时算起”.如：I haven’t heard any noise since I slept.Sleep 为持续性动词,sleep的动作结束时,即“醒来”时,这句应译为“我醒后还未听到任何声音”.John is now with his parents in New York,it is already three years since he was a teacher约翰现在和父母一起住在纽约,他不当教师已经三年了.本文开始出现的那个句子就可以译为“自从我离开上海,就再也没有收到他的信.”这种译法常被人们误用,我们不妨再多举几个例子看看：How long is it since you lived in Shanghai?你离开（没住在）上海多久了?It is half a month since he was a League member.他退团（不当团员）半个月了.It’s been quite some time since I was last in London我离开伦敦已很长时间了.比较：He has written to me frequently since I was ill.自从我病愈以来,他屡次给我写信.（从句谓语为状态动词） He has written to me frequently since I fell ill.自从我生病以来,他就屡次给我写信.（从句谓语为终止性动词）