since后面用过去式和完成式有什么不同
It has been two years since I was in this university.
为什么这句话不是翻译为“我上大学已经有两年了”？
如果要表达“我上大学已经有两年了”，是不是应该说：
It has been two years since I have been in this university.
最佳答案 2020-01-19 14:37
Since 引导时间状语从句
(1) 若since引导的状语从句的谓语动词是终止性动词(如go，come，leave，start，begin等)的过去时，则从句表示的时间是“从该动作开始的那一时刻起”。这是最常见的一种用法。如：
He has studied very hard since he came to our school.
自从来到我们学校，他学习就非常努力。
Great changes have taken place in our school since you left.
自从你离开这里，我们学校发生了很大的变化。
(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静态动词(如live，stay，study，learn，smoke，be等)的过去时，则从句表示的时间是“从该动作或状态的完成或结束时算起”。如：
I haven’t heard from him since he lived here.
这句话应译为：从他不住这儿起，我一直没有收到他的信。
I haven’t eaten snakes since I was a student at school.
was表示状态，因此该句可理解为：
I haven’t eaten snakes since I left school.
自从我毕业后就一直没吃过蛇。
试比较：
He has written to me frequently since I was ill.
自从我病愈以来，他经常给我写信。(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，他经常给我写信。(从句谓语为终止性动词)
(3) 若since引导的状语从句的谓语为持续性动词或静态动词的现在完成时，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：
He has written to me frequently since I have been ill.
这里have been ill表示状态的持续性，时间的起点应从：“开始生病”时算起。因此此句可理解为：“自从我生病以来，他经常给我写信。”
试比较：
I’ve written her 20 letters since I have been here.
自从我来到这，我已经给她写了20封信。(从开始算起)
I’ve written her 20 letters since I was here.
自从我离开这儿，我已经给她写了20封信。(从结束算起)
(4) It is + 段时间+ since... / It has been + 段时间+ since...表示“从„„起已有多长时间了”。两句型意思相同，前者是规范说法，后者是口语说法。
用法：since从句中常用一般过去时，若从句中是持续性动词的一般过去时，则表示该动作结束有多长时间了。如：
It is three years since he smoked.
他不吸烟已有3年了。
试比较：
It is three years since he began to smoke.
It is three years since he has smoked.
两句均意为：他吸烟已有3年了。
注意：在这种结构中，since引导的从句绝对不能用否定式的谓语动词来表示否定意义，
试比较：
他好久没学汉语了。
误：It is a long time since be didn’t study Chinese.
正：It’s a long time since he studied Chinese.
(studied为持续性动词，应从其动作结束时算起)(引自百度）
如果觉得我的回答对您有用，请随意打赏。你的支持将鼓励我继续创作！
其它 4 个回答
since引导的时间状语从句可以使用延续性动词和瞬间动词，但表示的意思不同。
since+延续性动动词时，可以用一般过去时态也可用现在完成时态。一般过去时态代表不在那个动作结束以后，如果是现在完成时态才代表自那个动作结束以后。
since+瞬间动词时，不论用一般过去还是现在完成时态都表达一个意思，即自从动作结束以后。
“我上大学已经有两年了。”应译为：
It is (has been) two years since I entered this university.
I entered this university two years ago.
I have been/studied in this university for two years.
It is for two years that I have been/studied in this university.
▲关于这个问题可参看“英语语法网”上的一篇文章。
http://www.yygrammar.com/Article/201501/3791.html
如果觉得我的回答对您有用，请随意打赏。你的支持将鼓励我继续创作！
It has been two years since I was in this university.
为什么这句话不是翻译为“我上大学已经有两年了”？
如果要表达“我上大学已经有两年了”，是不是应该说：
It has been two years since I have been in this university.
除了上面的表达还有下面几种表达
(1)I have been in this univeristy for two years.
(2)I was in this univeristy two years ago.
(3)I have been in this university since two years ago.
解答如下：
(1) It is /has been+时间段+since +主语+延续性/持续性动词+其他 表示从句这个动作结束了/停止了有多长时间。
It is /has been four years since he smoked.
他戒烟已经有了4年时间。
It is/has been five years since he lived here.
他不住在这里已经有5年了。
It is /has been two days since he was ill.（结束计时）
他病了已经有2天时间了
It is/has been two years since he studied English.
他已2年没有学习英文了。
(2) It is /has been+时间段+since +主语+终止性/瞬间动词+其他 表示从句这个动作开始了/进行了有多长时间。
It is/has been ten years since she left me.
自从她离开我已经十年了。
It is/has been five years since he left here.
他离开这儿已有五年了。
It is /has been two days since he fell ill.（开始计时）
他病已经有2天时间了。
(3) It is /has been+时间段+since +主语+have/has+过去分词+其他 表示从句这个动作开始/进行有多长时间。
It is/has been five days since he has been ill.
他生病已经有了5天了。
It is three years since he has smoked.
他吸烟已有3年了。
He has written to me frequently since I have been ill.
自从我生病以来， 他经常给我写信。
I’ve written her 20 letters since I have been here.
自从我来到这， 我已经给她写了20封信。(从开始算起)
since作连词引导时间状语从句的用法。
【1】若since引导的状语从句的谓语动词是终止性动词的过去时，则从句表示的时间是“从动作开始的那一时刻起”， 这是最常见的一种用法。
He has studied very hard since he came to our school.
自从他来到我们学校，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，则从句表示的时间是“从那个持续动作或状态结束时算起”。
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。
It is half a month since he was a League member.
他退团半个月了。
It's been quite some time since I was in London.
我离开伦敦已很长时间了。
He has written to me frequently since I was ill.
自从我病愈以来，他经常给我写信。（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，他就经常给我写信。
（从句谓语为终止性动词）
【3】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。
I haven't heard from him since he has lived there。
自从他住在那儿起，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。
Since I've been at this school, we have had three headmasters.
自从我到这所学校，我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。
比较下面句子：
He has written to me frequently since I have been ill.
自从我生病以来， 他经常给我写信。（开始算起）
I’ve written her 20 letters since I have been here.
自从我来到这， 我已经给她写了20封信。(从开始算起)
I’ve written her 20 letters since I was here.
自从我离开这儿， 我已经给她写了20封信。(从结束算起)
如果觉得我的回答对您有用，请随意打赏。你的支持将鼓励我继续创作！
It has been two years since I was in this university.
这句话应该翻译为：我离开这所大学已经有两年了。
如果要表达“我上大学已经有两年了”，应该说：
(1)It has been two years since I attended [went to] university.(口语)
(2)It is two years since I attended [went to] university.
(3)I have been in this university for two years.
-
《高考英语备考1号·速效编》
-
《高考英语备考1号·写作编》
-
《高中英语晨读晚记》
-
《高中英语错题笔记》
-
《零起点考大学英语》
-
