英语《since引导的时间状语从句》PPT课件.ppt

,Since引导的状语从句,若since引导的状语从句的谓语动词是终止或瞬间动词的过去时，则从句表示的时间是“从动作开始的那一时刻起”。e:He has studied very hardsince he came to our school.自从他来到我们学校，他学习就非常努力。,2、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 havent 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。Its 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）,Compare with,三、若since引导的状语从句的谓语为持续性动词的现在完成时,则表示动作和状态延续到现在（说话时刻），其表示的时间的起点应从动作发生之时算起。如：I havent heard from him since he has livedthere。这里has lived表示动作的持续性，时间的起点应从：“开始居住”时算起。因此此句可理解为“自从他（开始）住在那儿起，我就一直没收到他的来信”。Since we have owned a car,we have gone camping every year。自从我们自己有了汽车，我们每年都去野营。试比较：1.Since Ive been at this school,we have had three headmasters 自从我离开这所学校，他们已换了三个校长了。Since I was at this school,they have had three headmasters 自从我离开这所学校，他们已换了三个校长了。,关于since的用法的练习,The window is dirty.I know.It _ for weeks.（2004全国03）A.hasnt cleaned B.didnt clean C.wasnt cleaned D.hasnt been cleaned“for”加一段时间要用现在完成时，所以排除BC选项，由於“window”能“自己清洁”自己，即为被动语态，所以排除A选项，所以D选项为正确答案。,