现在完成时一
现在完成时是初中英语所涉及的八种主要时态之一,也是最难掌握的时态之一,而它又是中考必考的知识点,所以下面我们来归纳总结一下这个时态,以便同学们掌握得更好一些。
一. 现在完成时的构成和概念
现在完成时由“have(has)+动词的过去分词”构成。例:
I have seen the doctor. 我看过医生了。
He has finished his homework.
他已经完成作业了。
二. 现在完成时的基本概念有二:
1.表示过去发生的某一动作对现在造成的影响或结果。例如:
I have already posted my letters. (我已把信寄走了。)
“寄”信的动作是过去发生的,而现在的结果是“信不在我这儿了”。又如:
Have you found your ruler yet?
你已经找到你的尺子了吗?
I’ve just done my homework.
我刚做完家庭作业。
2.表示过去已经开始并持续到现在的动作或状态,可以和表示从过去某一时刻延续到现在(包括“现在”在内)的段时间状语连用。 例如:
I haven’t seen her these days.
这些天我一直没看见她。
(没看见她的这种情况,是从过去开始一直延续到现在。)
I’ve been here for just over two years.
我来这刚过两年。
How long has Jim been at this school?
吉姆在这个学校多久了?
*(1)由于现在完成时属于现在时态的范畴,因而不能和表示过去的时间状语(last week, yesterday, in 1990等)连用,但可以与already, never, ever, just, yet等副词连用。例如:不可以说:I’ve finished the work last week. 但可以说:I’ve already finished the work.
(2)由于现在完成时表示动作的延续过程,因而,那些不能表示延续动作的动词(又叫短暂性动词或终止性动词)用于此时态时,其肯定式不能同for或since引起的表示一段的时间状语连用。
例如:“他的母亲去世五年了。”这句话不可译为His mother has died for five years. 而应译成:His mother died five years ago. / His mother has been dead for five years.
因为“die”是瞬间动词,表示短暂的动作。
类似于这类的动词还有:go, come, join, leave, begin, start等表示短暂性的动作,无法表示动作的延续,需用它相对应的延续词来替换。
go / come /→be leave →be away
begin / start → be on buy → have
borrow → keep die → be dead
become →be join → be in / be a …
open →be open close → be closed
end → be over
例如:
这本书我买了两个星期了。
I’ve had the book for two weeks.
不能说have bought. 又如:
会议开始半小时了。
The meeting has been on (不可以说has started或has begun)for half an hour.
我们来了二十分钟了。
We have been here (不可以说come here)for 20 minutes.
如果现在完成时的谓语是动词否定式,虽然这类动词表示的是一个短暂性的动作,但可以和for或since表示的时间短语连用。例如:
We haven’t left home for a week.
我们有一周没出家门了。
I haven’t seen him since last week.
从上周我就没看见他。
(3)现在完成时态和一般过去时的区别:
现在完成时表示过去发生的动作对现在的影响或结果,强调的是现在的情况;而一般过去时只是单纯表示过去的动作或状态,和“现在”没有关系。例如:
I have opened the window.
我已把窗子打开(窗子是开着的)
I opened the window an hour ago.
一个小时前我打开窗子了。
(不考虑现在窗户是否开着。)
三. have(has)+过去分词+since /或for表示的时间短语。
for后面常加段时间,如three years, two hours, a year等。
例如:
He has been in the Party for a year.
他入党一年了。
I have been a teacher for ten years.
我当老师10年了。
since后可以加时间点或从句,从句的时态常为一般过去时,例:
He has been here since last week.
他从上个礼拜就来这了。
His sister has been away since two years ago.
他妹妹两年前就离开了。
I’ve been here since 1990.
我从1990年就来这了。
He has been a teacher since he left university.
他从离开大学就当老师。
I’ve been at this school since I came here.
我从来这就在这个学校。
He has work there since it opened in 1989.
1989年工厂开办以来,他就在那工作。
*since / for 表示的时间状语用于完成时,表示动作的持续,还有不同的表达法与此构成同义句。例如:
这所房子我买5年了。可以有以下几种表示法:
I have had the house for five years.
I have had the house since five years ago.
I bought the house five years ago.
It is five years since I bought the house.
Five years has passed since I bought the house.
四. “have (has)been to …”“have(has) gone to …”“have(has) been in …”的意义区别。
(1)Have you been to the Great Wall?
你去过长城吗?
I’ve been to Shanghai.
我去过上海。
His father has been to England.
他父亲去过英国。
“have (has)been to …”表示“去过…,人已回来。”
(2)His father has gone to England.
他父亲去英国了。
Where’s Mike?
Mike在哪?
He has gone to Paris.
他去巴黎了。
“have(has)gone to …”表示“去哪了…”,人不在说话人现场。
(3)They have been in England for half a year.
他们去英国半年了。
He has been in Shanghai for two weeks.
他去上海两周了。
“have(has)been in …”“去哪多久……”和段时间连用,现在完成时比较复杂。使用时既要注意动词的改变、时间的选择,又要和一般过去时区别开,不是结束性动词不可以用于现在完成时,而是其肯定式不能和段时间连用,这一点要特别注意。
五、终止性动词表示的动作极其短暂,不能持续。因此,不可与表示一段时间的状语连用(只限肯定式)。如: (1)他死了三年了。
误:He has died for three years.
正:He has been dead for three years. 正:He died three years ago.
正:It is three years since he died. 正:Three years has passed since he died.
(2)他来这儿五天了。
误:He has come here for five days.
正:He has been here for five days. 正:He came here five days ago.
正:It is five days since he came here. 正:Five days has passed since he came here.
(1)、(2)句中的die、come为终止性动词,不能与表示"段时间"的状语连用。那么,应如何正确表达呢?可以采用下面的四种方法:
(1)将句中终止性动词转换为相应的延续性动词,如上面两例中的第一种正确表达方式。下面列举几例:leave→be away, borrow→keep, buy→have, begin/start→be on, die→be dead, move to→live in, finish→be over, join→be in/be a member of, open sth.→keep sth. open, fall ill→be ill, get up→be up, catch a cold→have a cold。
(2)将句中表示"段时间"的状语改为表示过去确定时间的状语,如下面两例中的第二种正确表达方式。
(3)用句型"It is+段时间+since..."表达原意,如上面两例中的第三种正确表达方式。
(4)用句型"时间+has passed+since..."表达原意,如上面两例中的第四种正确表达方式。
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