比較過去時(shí)與現(xiàn)在完成時(shí)
1）過去時(shí)表示過去某時(shí)發(fā)生的動(dòng)作或單純敘述過去的事情,強(qiáng)調(diào)動(dòng)作；現(xiàn)在完成時(shí)為過去發(fā)生的,強(qiáng)調(diào)過去的事情對(duì)現(xiàn)在的影響,強(qiáng)調(diào)的是影響.
2）過去時(shí)常與具體的時(shí)間狀語連用,而現(xiàn)在完成時(shí)通常與模糊的時(shí)間狀語連用,或無時(shí)間狀語.
一般過去時(shí)的時(shí)間狀語:
yesterday,last week,…ago,in1980,in October,just now,具體的時(shí)間狀語
共同的時(shí)間狀語:
this morning,tonight,this April,now,once,before,already,recently,lately
現(xiàn)在完成時(shí)的時(shí)間狀語
for,since,so far,ever,never,just,yet,till / until,up to now,in past years,always,
不確定的時(shí)間狀語
3）現(xiàn)在完成時(shí)可表示持續(xù)到現(xiàn)在的動(dòng)作或狀態(tài),動(dòng)詞一般是延續(xù)性的,如live,teach,learn,work,study,know.
過去時(shí)常用的非持續(xù)性動(dòng)詞有come,go,leave,start,die,finish,become,get married等.
舉例：
I saw this film yesterday.
（強(qiáng)調(diào)看的動(dòng)作發(fā)生過了.）
I have seen this film.
（強(qiáng)調(diào)對(duì)現(xiàn)在的影響,電影的內(nèi)容已經(jīng)知道了.）
Why did you get up so early?
（強(qiáng)調(diào)起床的動(dòng)作已發(fā)生過了.）
Who hasn't handed in his paper?
（強(qiáng)調(diào)有卷子,可能為不公平競爭.）
She has returned from Paris.
她已從巴黎回來了.
She returned yesterday.
她是昨天回來了.
He has been in the League for three years.
(在團(tuán)內(nèi)的狀態(tài)可延續(xù))
He has been a League member for three years.
(是團(tuán)員的狀態(tài)可持續(xù))
He joined the League three years ago.
( 三年前入團(tuán),joined為短暫行為.)
I have finished my homework now.
---Will somebody go and get Dr.White?
---He's already been sent for.
句子中如有過去時(shí)的時(shí)間副詞（如 yesterday,last,week,in 1960）時(shí),不能使用現(xiàn)在完成時(shí),要用過去時(shí).
（錯(cuò)）Tom has written a letter to his parents last night.
（對(duì)）Tom wrote a letter to his parents last night.
過去完成時(shí)
1） 概念：表示過去的過去
----|-------|-----|---->其構(gòu)成是had +過去分詞構(gòu)成.
那時(shí)以前 那時(shí) 現(xiàn)在
2） 用法
a.在told,said,knew,heard,thought等動(dòng)詞后的賓語從句.
She said (that) she had never been to Paris.
b.狀語從句
在過去不同時(shí)間發(fā)生的兩個(gè)動(dòng)作中,發(fā)生在先,用過去完成時(shí)；發(fā)生在后,用一般過去時(shí).
When the police arrived,the thieves had run away.
c.表示意向的動(dòng)詞,如hope,wish,expect,think,intend,mean,suppose等,用過去完成時(shí)表示"原本…,未能…"
We had hoped that you would come,but you didn't.
3) 過去完成時(shí)的時(shí)間狀語before,by,until ,when,after,once,as soon as.
He said that he had learned some English before.
By the time he was twelve,Edison had began to make a living by himself.
Tom was disappointed that most of the guests had left when he arrived at the party.
典型例題
The students ___ busily when Miss Brown went to get a book she ___ in the office.
A.had written,left B,were writing,has left C.had written,had left D.were writing,had left
答案D."把書忘在辦公室"發(fā)生在"去取書"這一過去的動(dòng)作之前,因此"忘了書"這一動(dòng)作發(fā)生在過去的過去,用過去完成時(shí).句中when表示的是時(shí)間的一點(diǎn),表示在"同學(xué)們正忙于……"這一背景下,when所引導(dǎo)的動(dòng)作發(fā)生.因此
前一句應(yīng)用過去進(jìn)行時(shí).
注意：had no … when 還沒等…… 就……
had no sooner… than 剛…… 就……
He had no sooner bought the car than he sold it.