初中英语语法之现在完成时的用法

现在完成时的用法

一、现在完成时的意义

1．现在完成时表示的是在过去某个时间开始并持续到现在的动作/状态；

2过去的动作或状态对现在造成的影响或结果。

They have worked in the factory for about ten years． (现在还在这里工作)

I have had my lunch．（我现在不饿）

二、基本句型结构：have /has (助动词)+done(过去分词)

现在完成时的肯定陈述句结构：

I/You/They/We have worked……   

 He/She has worked……

现在完成时的否定结构：

I/You/They/We haven’t  worked…    

He/She hasn’t  worked…

现在完成时的一般疑问句结构：

Have I/You/They/We worked …?   

Has he/she worked…?

肯定的简略回答是：

Yes，主语＋have/has．

否定的简略回答是：

No，主语＋have/has not……

如：I have seen the film． 

→Have you seen the film？ 

Yes， I have．/No， I haven’t．

三、常用时间状语

for, since;so far,up to now, by now; ever, never, just, before, yet, already；till/until, in the past few years; recently, lately; …… times; how long等。

四．学习现在完成时必须要掌握的几个概念和技能

（一）一般过去时与现在完成时的区别：

1）二者意义不同：一般过去时表示过去某时发生的动作或单纯叙述过去的事情，与现在的状况无关；现在完成时，强调过去的事情对现在的影响，强调的是影响。

I saw this film yesterday．　

强调看的动作发生过了。

I have seen this film． 

强调对现在的影响，电影的内容已经知道了。

2）两个时态的时间状语不同：

一般过去时的时间状语：

yesterday, last month,three days ago, in1999, in October, just now等 

现在完成时的时间状语：

for+时间段, since+时间点, so far, ever, never, just, yet, up to now, in the past few years, recently等。        

（二）延续动词与瞬间动词的区别：

延续动词表示发生之后能够延续的动作

如：learn, work, stand, lie, know, walk, keep, have, wait, watch, sing, read, sleep, live, stay等。延续性动词可以与表示时间段的状语连用。

表示时间段的短语有：for+一段时间：for 2 years; since从句,since he came here;

since+时间点名词,since last year, since 5 days ago; how long; for a long time等。

非延续性动词也称终止性动词、瞬间动词,发生后立即结束。不能与表示一段时间的状语连用。 

如：open, die, close, begin, finish, come, go, move, borrow, lend, buy等。

非延续性动词在肯定句中与表示时间点的状语连用

如：two years ago; at 5 o’clock;

注意：如果终止动词和时间段同时出现就是错句，必须要把终止动词变为延续动词。

The old man died for 4 years．（×）     

The old man has been dead for 4 years． (√)  

He joined the Party 2 since two years ago．（×）    

He has been in the Party for 2 years．      (√) 

（三）英语延续动词与非延续动词如何转换 ：

leave — be away 

borrow — keep          

buy — have  

begin/start — be on      

die — be dead 

finish — be over 

open sth — keep sth open 

fall ill —  be ill         

get up—be up

catch a cold — have a cold  

come here — be here      

go there — be there    

become — be   

come back — be back      

fall asleep — be asleep   

get to/ arrive/reach — be (in)  

leave — be away from    

get to know — know

go (get) out →be out  

put on→ wear

（四）since和for的区别：

since 用来说明动作起始时间— “自从……” 

for用来说明动作延续时间长度— “长达……”

如：

I have lived here for more than twenty years． 

I have lived here since I was born．

My aunt has worked in a company since 1949．

I have not heard from my uncle for a long time．

（五）have been to /have gone to /have been  in的区别：

He went to Shanghai last week 

上周他[做了一件事：那就是]去了上海

He has been to Shanghai．

他(曾经)到/去过上海 [在他人生中曾经有过这样的经历,但他人现在肯定不是在上海而是回来了]

He has gone to Shanghai．

他已经去上海了 [也许刚动身出发,也许已经到了,也许还在路上,反正他人不在这里]

He has been in Shanghai for 10 years．

他呆在上海迄今为止已经10年了 [现在还在上海没有离开呢]

He lived in Shanghai for 10 years．

以前他在上海住过10年 [现在不在上海了]

（六）现在完成时的常见句型：

①在表示将来的时间状语和条件句中用现在完成时代替一般现在时

I won’t believe you until I have seen you in the jar with my own eyes．

②It’s/This’s the +形容词最高级+名词+that +现在完成时的从句

This is the fantastic film that I have ever seen．

③It’s +基数词+years/hours等+since……

=It has been+基数词+years/hours等+since……

= ⑥基数词+years/hours等 has passed +since……

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