since的用法

 　 1) since +過(guò)去一個(gè)時(shí)間點(diǎn)　(如具體的年,、月、日期,、鐘點(diǎn),、1980, last month, half past six)。

　 I have been here since 1989.

　　 2) since +一段時(shí)間+ ago

　 I have been here since five months ago.

　 3) since +從句　

　 Great changes have taken place since you left.

　 Considerable time has elapsed since we have been here.

　 4) It is +一段時(shí)間+ since從句

　 It is two years since I became a postgraduate student.

since的用法主要有兩點(diǎn)：一是表示“自從……以來(lái)”,，二是表示“既然”之意,。但如果只了解詞的含義，而不了解其用法,，在使用時(shí)就會(huì)造成錯(cuò)誤,。例如：I have not heard from him since I lived in Shanghai.

不少人會(huì)望文生義,，將該句譯為：“自從我住在上海以來(lái)，就再也沒(méi)有收到他的信了,。”而實(shí)際上這個(gè)句子的譯文并非如此,，那么正確的含義是什么呢？

下面談?wù)?span lang=EN-US>since作連詞引導(dǎo)時(shí)間狀語(yǔ)從句的用法,。

一,、若since引導(dǎo)的狀語(yǔ)從句的謂語(yǔ)動(dòng)詞是終止性的過(guò)去時(shí)，則從句表示的時(shí)間是“從動(dòng)作開(kāi)始的那一時(shí)刻起”,。如：

He has studied very hard since he came to our school.自從他來(lái)到我們學(xué)校,，他學(xué)習(xí)就非常努力。

We have been missing them since they left here自從他們離開(kāi)這里,，我們就一直很想念他們,。

這是最常見(jiàn)的一種用法，此處不再多述,。

二,、若since引導(dǎo)的狀語(yǔ)從句的謂語(yǔ)動(dòng)詞是持續(xù)性動(dòng)詞或表示狀態(tài)的動(dòng)詞的過(guò)去時(shí)時(shí)，則從句表示的時(shí)間是“從那持續(xù)動(dòng)作或狀態(tài)結(jié)束時(shí)算起”,。如：

I haven’t heard any noise since I slept. Sleep 為持續(xù)性動(dòng)詞,，sleep的動(dòng)作結(jié)束時(shí)，即“醒來(lái)”時(shí),，這句應(yīng)譯為“我醒后還未聽(tīng)到任何聲音”,。

John is now with his parents in New York, it is already three years since he was a teacher約翰現(xiàn)在和父母一起住在紐約，他不當(dāng)教師已經(jīng)三年了,。

本文開(kāi)始出現(xiàn)的那個(gè)句子就可以譯為“自從我離開(kāi)上海,，就再也沒(méi)有收到他的信。”這種譯法常被人們誤用,，我們不妨再多舉幾個(gè)例子看看：

How long is it since you lived in Shanghai?你離開(kāi)（沒(méi)住在）上海多久了,？

It is half a month since he was a League member.他退團(tuán)（不當(dāng)團(tuán)員）半個(gè)月了。

It’s been quite some time since I was last in London我離開(kāi)倫敦已很長(zhǎng)時(shí)間了,。

比較：He has written to me frequently since I was ill.自從我病愈以來(lái),，他屢次給我寫(xiě)信。（從句謂語(yǔ)為狀態(tài)動(dòng)詞）

He has written to me frequently since I fell ill.自從我生病以來(lái),，他就屢次給我寫(xiě)信,。（從句謂語(yǔ)為終止性動(dòng)詞）

三、若since引導(dǎo)的狀語(yǔ)從句的謂語(yǔ)為持續(xù)性動(dòng)詞的現(xiàn)在完成時(shí),，則表示動(dòng)作和狀態(tài)延續(xù)到現(xiàn)在（說(shuō)話時(shí)刻）,，其表示的時(shí)間的起點(diǎn)應(yīng)從動(dòng)作發(fā)生之時(shí)算起。如：

I haven’t heard from him since he has lived there。

這里has lived表示動(dòng)作的持續(xù)性,，時(shí)間的起點(diǎn)應(yīng)從：“開(kāi)始居住”時(shí)算起,。因此此句可理解為“自從他（開(kāi)始）住在那兒起，我就一直沒(méi)收到他的來(lái)信”,。

Since we have owned a car, we have gone camping every year,。自從我們自己有了汽車，我們每年都去野營(yíng),。

試比較：1. Since I’ve been at this school, we have had three headmasters.自從我到這所學(xué)校,，我們已換了三個(gè)校長(zhǎng)了。

Since I was at this school, they have had three headmasters.自從我離開(kāi)這所學(xué)校,，他們已換了三個(gè)校長(zhǎng)了,。

2.He has never been to see me since I have been ill. 自從我生病以來(lái)，他從未來(lái)看過(guò)我,。

He has never been to see me since I was ill. 自從我病愈以來(lái),，他從未來(lái)看過(guò)我。

由此可見(jiàn),，since引導(dǎo)的從句持續(xù)動(dòng)詞的一般過(guò)去時(shí)和現(xiàn)在完成時(shí)所表示的意思恰好相反,。換言之，前者以肯定的語(yǔ)法形式反映著否定的邏輯內(nèi)容,，而后者的形式與內(nèi)容是一致的,。

至于It is +一段時(shí)間+since…的句型與It has been +一段時(shí)間+since…意思相同。前者是規(guī)范說(shuō)法,，后者是口語(yǔ)說(shuō)法,。

應(yīng)注意的是，在這種結(jié)構(gòu)中,，since引導(dǎo)的從句絕對(duì)不能用否定式的謂語(yǔ)動(dòng)詞來(lái)表示否定意義,，下面兩句都錯(cuò)了：

It is a long time since he didn’t study English.

It’s two months since you didn’t come to see me.

正確的說(shuō)法為：

It’s a long time since he studied English 他好久沒(méi)學(xué)英語(yǔ)了,。

You haven’t come to see me for two months. 你有兩個(gè)月沒(méi)來(lái)看我了,。