现在完成时态的讲解
(2011-09-20 14:29:02)
标签:
杂谈 |
般过去时和现在完成时的区别
一 从概念上区别一般过去时与现在完成时
如:I have cleaned our classroom. 我已经打扫了教室。
现在教室里很干净,“过去打扫”这一动作对目前产生的结果。(现在完成时)
I cleaned our classroom just now. 刚才我打扫了教室。
不涉及教室目前是否干净。(一般过去时)
二 从时间状语上加以区分
现在完成时属于“现在”时间范围。因而不能与表示过去的时间状语连用:一般过去是表示过去时间里发生的动作,不能与表示和现在时间有联系的时间状语连用。
如:Danny and Brian have been in China since 2003.
如何使用现在完成时
一、现在完成时的构成
(一)肯定式
主语+助动词have /has +过去分词+其它
说明:这里的have /has是助动词,没有什么具体意义。当主语是第三人称单数时助动词用has,其余人称一律用have。 has,have的缩略式分别为's或've。规则动词过去分词的构成与过去式的构成方式一样,不规则动词可参看不规则动词表。实例:
1)I've just copied all the new words .我刚抄写了所有的生词。 (表示不要再抄了)
2)She has lost her books .她丢失了她的书。 (表示到目前为止还没有找到)
(如果用过去时:She lost her books . 则强调书是过去丢的这一动作,而不知现在有没有找到)
3)We've just cleaned the classroom .我们刚好打扫了教室。(表明现在教室是干净的)
(二)否定式
主语+助动词have /has+not+过去分词+其它
说明:现在完成时构成否定句时,只需在助动词have /has后面加not就行。have not,has not的缩略式分别为haven't ,hasn't。另外,肯定句中有some,already时,改为否定时要分别改成any,yet。实例:
1)I haven't finished my homework yet.我还没有完成我的作业。
2)She hasn't travelled on a train .她没有坐火车旅行过。
3)We have never spoken to a foreigner.我们从来没有和外国人说过话。
注:有时not可以用never代替,表示“从来没有”的意思。又如:
4)I have never seen him before.以前我从来没有见过他。
(三)一般疑问式
助动词Have /Has +主语+过去分词+其它 ?
说明:把陈述句中的have或has放到句首,句末打问号,同时把句中的some ,already改为any ,ye t就构成了一般疑问句。肯定回答用“Yes ,主语+have/has.否定回答用“No,主语+haven't/hasn't.”有时也可以用“No,not yet./No ,never./No,not even once.”等。实例:
1)—Have you ever made dumplings ?你曾经做过饺子吗?
2)—Has she ever been abroad ?她曾经出过国吗?
3)—Have they found the lost books yet ?他们已经找到了丢失的书吗?
注意:当句中有否定词not ,hardly(几乎不),never的时候,在改为反意疑问句时,附加部分用肯定形式。例如:You have never come to our school ,have you ?你以前从来没有来过我们学校,是吗?
二、现在完成时的用法
(一)现在完成时的用法1:表示过去发生或已经完成的某一动作对现在造成的影响或结果。此时,常与时间副词already(已经) ,yet(还、已经) ,just(刚刚、仅仅) ,ever(曾经) ,never(从不) ,before(以前)等连用。这几个副词的用法如下:
1.already意为“已经”,通常用于肯定句中,可放在助动词之后,过去分词之前,也可以放在句末。实例:
1)I've already read this book.
2)I've washed my clothes already.我已经洗了衣服。
注意:在表示吃惊或明知故问等感情色彩时,already也可用于(口语)疑问句中。实例:
3)Have you met him already ?你(真的)已经见过他了?
2.yet用在疑问句中意为“已经”,用在否定句中意为“还”,常放在句末。实例:
1)—Has he found his watch yet ?他已经找到他的手表了吗?
2)The woman hasn't found her dog yet .
3.just意为“刚刚”,表示行为刚刚过去,常放在助动词与过去分词之间。实例:
4.ever意为“曾经”,用于疑问句或否定句中,放在助动词与过去分词之间。实例:
5.never意为“从来没有”常与before连用(before要放在句尾,而never多放在助动词与过去分词之间。实例:
6.before意为“以前”,指过去不确定的某个时间,总是放在句末,不受句型的限制。实例:
(二)现在完成时用法二2——持续性用法(肯定句,疑问句中谓语动词必须是延续性动词):表示过去已经开始,持续到现在的动作或状态。此时常与“for +一段时间或“since+过去的点时间或从句(从句用一般过去时)以及so far(到目前为止)等时间状语连用。
for + 段时间
since +点时间
1)I've lived here since 1990.自从1990年以来我就住在这里。
= I've lived here for 13 years.
2)I haven't seen him for three years .我三年没有看见他了。
3)Mr Wang has worked in the factory since he came to the city .
4)She's been at this school since five years ago.
注意:①在这类句子的肯定句和疑问句中谓语动词必须用延续性动词。短暂性动词由于动作不能持续,故不能与for(达到;累计)或since(自从。。。到现在)引出的时间状语连用。
②对for和since引导的时间状语提问要用How long
1)
误:He has joined the League for two years.
正:He has been a League member for two years.
2)我买这辆自行车三年了。
误:I have bought this bike for three years.
正:I have had this bike for three years.
2)
die
borrow
get
up
有人可能会问:一般过去时和现在完成时所表示的动作都发生在过去,那么这两种时态有什么区别呢?
☆答:①一般过去时与具体的表示过去时间状语如:yesterday连用;强调动作在过去发生,与现在无关。
例: He saw the film last night. (过去时,表示他昨晚看过那部电影了,现在不知还要不要再看一次)
He has (ever) seen the film before.(现在\完成时,表时他已看过那部电影,现在不想再看了)
巩固练习:
I.按要求转换下列各句,每空一词。
1、He has already finished his homework.(改为否定句)
2.They have found the lost books already.(改为一般疑问句,并作否定回答)
3.Julia has not got home from school yet.(改为肯定句)
4.You have never been to Shanghai before,_________ _________ ?(改为反意疑问句)
5.
6.Mr Wang began to teach English in this school in 1999.(改为同义句)
7. He
8. They have lived here since 3 years
ago.
II.选择正确答案。
(
(
(
(
11.11 用于现在完成时的句型
1)It is the first / second time…. that…结构中的从句部分,用现在完成时。
It is the first time that I have visited the city.
It was the third time that the boy had been late.
2)This is the… that…结构,that 从句要用现在完成时.
This is the best film that I've (ever) seen.
这是我看过的最好的电影。
This is the first time (that) I've heard him sing. 这是我第一次听他唱歌。
典型例题
(1) ---Do you know our town at all?
---No, this is the first time I ___ here.
A. was B. have been C. came D. am coming
答案B. This is the first time 后面所加从句应为现在完成时,故选B。
(2) ---Have you ____ been to our town before?
---No, it's the first time I ___ here.
A. even, come B. even, have come C. ever, come D. ever, have come
答案D. ever意为曾经或无论何时,反意词为never,此两词常用于完成时。 This is the largest fish I have ever seen. It is / was the first time +that-clause 的句型中,从句要用完成时。
注意:非延续性动词的否定形式可以与表示延续时间的状语连用。即动作不发生的状态是可以持续的。
(错)I have received his letter for a month.
(对)I haven't received his letter for almost a
month.
现在完成时点滴
初中英语共涉及八种主要时态,在中考当中现在完成时的占分比例比较大。因此学好现在完成时对于初中生来说至关重要。下面我们谈一下如何学好这个时态:
一、现在完成时的基本构成
现在完成时由“主语+have/has+V过去分词”构成。“have /has”如何使用需记清。当主语是I,you和复数名词或代词时要用have;单数主语后跟has。也就是说have/has需同主语的人称或数保持一致。
二、现在完成时的基本用法
1.动作开始于过去,结束于过去,但和现在的情况关系密切。例如:
--Can I help you with your homework?
--Thank you all the same. I have finished it already?
从这里可以看出,“做作业”这个动作发生于过去,而且也结束于过去,但和现在关系密切。“Thank you all the same.”暗指无须帮忙。现在由于做完了(finished)已不用帮忙。强调的是“做完”这个动作对现在的影响。
2.动作发生于过去一直延续到现在。这个动作可能是多次发生,也可能是表示某种状态或习惯性动作。例如:
I have lived here since 1979.
He has worked in Beijing for 20 years.
在这个用法中,有一点需要我们特别注意,即含有中止或短暂意义的词不能跟一段时间搭配。例如:我们如果想表达“他已离开此地两天了。”我们不能说“He has left for two days.”而应说成“He has been away for two days.”像此类型的单词不多,大致有:begin,end,come,go,leave,join,die等。
三、现在完成时的标志词
是否使用现在完成时不仅可以通过了解句子的汉语意思套用其基本用法,还可以通过观察时间标志词。和现在完成时态连用的时间状语主要有以下三种:
1.句中出现 just,never,ever, already, yet等词时句子一般使用现在完成时。例如:
He hasn't found the answer to the question yet.
2.for +一段时间或since+点时间或引导时间状语从句(一般多为过去时)。例如:
He has been a teacher for 20 years.
I have known him since we were little-boys.
3.so far(到目前为止),in the past/last+表示一段时间的词语。例如:
I haven't seen him so far.
He hasn't talked with me in the past/three days.
当然这种方法并不是绝对的,有时也有意外情况发生。因此还需要同学们认真仔细的辨别。但我相信只要大家用心学习,现在完成时不会成为我们英语学习道路上的绊脚石。
现在完成时 Present perfect
接触一:肯定句式
现在完成时的肯定句式是“have(has)+过去分词”。如:
① We have just finished our
homework.
注意:1)该句式中的have或has是助动词,has用于第三人称单数,其它人称一律用have。
2)该句式中have(has)和过去分词之间可用just插入。
3)把该句式译成汉语时,往往用“已经”、“刚刚”、“过”或“了”等。
接触二:疑问句式
现在完成时的一般疑问句式是把助动词have或has提到主语之前。如:
③ Have you read this story book yet?
特殊疑问句及反意疑问句结构如下:
④ What have you done with my bike?
⑤ You've read this story book, haven't you?
注意:1)现在完成时的一般疑问句往往在句末加yet。
2)把现在完成时的一般疑问句译成汉语时,往往译成“……过吗?”、“已经……了吗?”等。
3)其肯定回答用“Yes,...have(has).”,否定回答用“No,...haven't(hasn't).”,有时用“No,not yet.”或“No,never.”。
接触三:否定句式:现在完成时的否定句式是“haven't(hasn't)+过去分词”。如:
⑥ We haven't studied Unit 2
yet.
注意:1)现在完成时的否定句句末往往加yet。2)否定句常译为“还没有……”等。
现在完成时巩固练习(一)
I. 用所给动词的适当形式填空。
1. I______never______(speak)to a foreigner.
2. —______Tom______(return)the library book? —Yes,he has.
II. 按要求转换下列各句,每空一词。
1. He has found nothing in the room.(改为一般疑问句)
2. I have already finished the work.(改为否定句)
3. She has got a notebook.(对划线部分提问)
4. They've never learned Japanese,_______ ________(改为反意疑问句)
接触四:用法之一:现在完成时表示过去发生或完成的某一动作对现在造成的影响或结果。如:
Have you read that story?你读过那个故事吗?
(“读”这一动作发生在过去,对现在造成的影响是:是否知道故事的内容。)
I have bought two apples. 我买了两个苹果。
(“买”这一动作发生在过去,对现在造成的结果是:拥有两个苹果。)
在学习这一概念的同时,还应注意常与现在完成时连用的几个副词:already,just,ever,yet,never等。already,just多用于肯定句中,ever,yet,never多用于疑问句和否定句中。如:
I have already finished my homework.我已经做完家庭作业了。
He has just had his meal.他刚吃过饭。
Have you ever sung this English song?你曾唱过这首英文歌吗?
They haven't started yet.他们还没有动身。
We have never heard of it.我们从来没有听说过这件事。
接触五:用法之二 :表示过去已经开始,一直持续到现在的动作或状态。
注:这一用法即现在完成进行时的用法
因为表示的是持续的动作或状态,所以使用的动词通常是延续性动词:be, stay, study, wait, keep, have… 等;
使用的时间状语通常由for或since 引导,但二者后接的词有所不同:
for后常跟一个时间段,指某个动作到现在为止已持续了多长时间,如for three years, for half an hour等。 since 作介词,后面可以接一个时间点,如since 1980,也可以接“一段时间+ago”,
如: since three years ago, since two months ago等。
since 还可用作连词,引导一个过去时态的时间状语从句。
如:We have known each other since we went to college.
非延续性动词不能直接和for 或since 连用,但我们可以找一个相应的延续性动词或动词短语来替换这些非延续性动词,如:
come→be, come to→be in / at, go out→ be out, leave→be away, begin / start→be on, stop→ be over,buy→ have, borrow→ keep, open→be open, close→be closed, join→be a member of, die→be dead, catch a cold→have a cold, get to know→know, become a teacher →be a teacher, fall asleep→be asleep, fall ill→ be ill等。
句型It is the first (second, third...) time that...的that从句中,
谓语动词须用现在完成时,表示到说话时为止动作发生过几次。如:It is the first time that I have been here. 接触六:现在完成时与一般过去时的用法比较
现在完成时表示过去的动作对现在造成的影响;一般过去时表示动作发生的时间在过去。试比较:
The plane has arrived . 飞机已经来了。(说明现在的情况:飞机在这儿。)
The plane arrived a quarter of an hour ago. 飞机是一刻钟以前抵达的。(强调动作发生的时间在过去。)
接触七:have been in, have been to 与have gone to 的用法
1. have(has) been in 意为“已经在某地呆了多长时间”,常与表示一段时间的状语连用。如:
2. have(has) been to意为“曾经去过某地”,表示现在已经不在那里了。
可与just, ever, never等连用。如:
3. have(has) been to 后面可接次数,表示去过某地几次。如:
4. have(has) gone to 意为“到某地去了”,表示到了某地或正在去某地的途中。
总之,说话时该人不在现场,一般不用第一、第二人称代词作句子的主语。如:
现在完成时巩固练习(二)
下列各句均有一处错误,请指出并改正。
1. So far we learned about six hundred English words.
2. I've been in Australia twice.
3. —Have you had your lunch? —No yet.
接触八:常用于现在完成时的时间状语
除了我们讲过的already, yet, still,just, ever, never, since短语和 for短语外,还有许多时间
状语常用于现在完成时,我们要留心将它们和一般过去时的时间状语区分开来:
1. lately, recently是完成时的时间状语;just now 有a moment ago 之意,是过去时的时间状语。如:
Have you heard from your family
lately/recently?
2. in the past few years 意思是“过去几年来”,常用于完成时中;
in the past意思是“在过去”,常用于过去时中。 如:
3. ever since then与from then on / after that 都有“打那以后”之意,
但前者常用于完成时,而后两者常用于过去时。如:
She\'s lived here ever since then. I didn\'t hear of Jim from then on/after that.
4. before 通常用于完成时;...ago通常用于过去时。如:
I have never been to Japan before. She went to Japan two years ago.
5. so far“到目前为止”, these days“这些天来”也是现在完成时常见的时间状语。如:
So far, no man has travelled farther than the moon. What have you done these days?
接触八:过去分词有规则与不规则两种。
规则的变化形式与动词的过去式一样。不规则就需要记忆了
不规则动词过去式和过去分词
A. 原型:过去式和过去分词完全不同
drink---drank----drunk
B. 过去式与过去分词完全相同
bright----brought----brought
buy----bought----bought
tell----told----told
send----sent----sent
burn----burnt----burnt
feel----felt----felt
sweep---slept----slept
lose----lost----lost
sit----sat----sat
spit----spat----spat
make----made----made
find----found----found
understand----understood----understood
C.原型与过去分词相同
come----came----come
D.原形与过去式和过去分词完全相同
cast----cast----cast
let----let----let
第二种形式理解 现在完成时
现在完成时常被称为“与现在有联系的过去”,因此它不能与明确的过去时间状语连用。
现在完成时的用法
1)
①
这是现在完成时的“已完成”用法,表示动作或过程发生在说话之前就已完成,并与现在有联系。这种联系实际上就是“过去的动作”对现在的影响或产生的结果。
I have bought a pen.
The temperature has increased by
10℃.
Air pollution has taken the lives of many people.
空气污染已经夺去了很多人的生命。
②与现在完成时“已完成”用法连用的时间状语
★不确定的过去时间状语:already, yet, before, recently, lately等。
I've seen the film
before.
Have you been there lately?
★包含现在时间在内的时间状语:now, just, today, this morning, this week, this year等。
I have just finished the letter
now.
You have just missed the
bus.
Has he done much work today?
2)表示经历的现在完成时:调过去某一时刻到说话时这段时间中的经历。
Have you ever been to the Great
Wall?
I have visited Beijing at least ten
times
She has never spent a holiday at the seaside. 她从未到海滨度过假。
①是现在完成时的“未完成”用法,
表示一个动作或状态从过去某时开始,持续到现在,可能要继续下去。
He has loved fishing for a long time.
I have lived here for more than thirty years.
②与现在完成时"未完成"用法连用的时间状语
与其连用的往往是指一段时间的状语以具体表示某一动作或状态持续了多久。
★since + 具体时间,表示动作或状态从何时开始。
Since then, he has developed another bad habit.
自那以后他养成了另一个坏习惯。
He hasn't been home since he
graduated.
★for + 一段时间,表示动作或状态持续了多久。
We have worked here for
ages.
There has been no rain here for nearly two months.
★until now, up till now, so far, up to the moment,到目前为止。
I have not seen him so
far.
Up to the present, everything has been
OK.
★in/during the past/last five years, 在刚刚过去的5年里。
He has been away from school during the last two weeks.
In the past few years they have finished several projects.
★all the while, all day 一直,一整天。
She has been busy all
day.
现在完成时和一般过去时的比较
①两者都可表示过去发生过的动作,但前者表示的是过去的动作对现在的影响,
而后者则只是表示过去有这一动作的事实。
He locked the
door.
He has locked the
door.
Who turned on the
light?
谁开的灯?
Who has turned on the light?
②
现在完成时表示该动作仍在继续,而一般过去时则说明该动作现已终止。
He has lived in Beijing for four years.
他在北京住了四年了。
He lived in Beijing for four years.
他曾在北京住了四年。
现在完成进行时Present perfect continuous tense
一、基本概念
1 定义:表示动作从过去某一时间开始,一直延续到现在,可能还要继续下去。
常和all this time, this week, this month, all night, all the morning, recently等状语以及since和for引导的状语连用。
2 构成:have/has + been + 动词的现在分词(V-ing)
3基本句型:
Have you been working? Yes, I/we have. No, I/we haven’t.
2) He/She/It has been working.
Has he/she/it been working? Yes, he/she/it has. No, he/she/it hasn’t.
3) We/You/They have been working.
Have they been working? Yes, they have. No, they haven’t.
注: 现在完成进行时基本上没有否定结构
二、现在完成时和现在完成进行时的区别
在与表示一段时间的状语(for, since短语)连用时,两种时态可以互换使用
I have been studying English for over two years
= I have studying English for over two years
但在口语中倾向于用现在完成进行时。
在不用表示一段时间的状语的情况下,现在完成进行时和现在完成时不可以随便互换使用:
(1)现在完成进行时更强调动作的延续性,现在完成时往往没有。试比较:
(a)句的意思是他们在加宽马路,但尚未完工。(b)句的意思则是已完工了。
(2)在不用时间状语的情况下,现在完成进行时表示动作仍在进行。
而现在完成时则表示动作在过去已结束。如:
The students have been preparing for the exam.(还在进行)学生们一直在准备考试。
The students have prepared for the exam.(已经结束)学生们为考试作了准备。
(3)有些表示状态,感情,感觉的动词如:have, exist, like, hate, hear, know, sound等动词不能用于现在完成进行时,但可用于现在完成时。如:
They?ve known each other since 1970.自从1970年起他们就相互认识了。
(4) 现在完成进行时可以表示动作的重复,而现在完成时一般不表示重复性。
Have you been meeting him recently?你最近常和他见面吗?
Have you met him
recently?
(5) 现在完成进行时比较生动,有时含有明显的感情色彩,而现在完成时往往只说明一个事实,一种影响或结果,平铺直叙,没有什么感情色彩可言。如:
What have you been doing?(a)
(a)句表示惊异。(b)句只是一个问题。
I have been waiting for you for two hours. 我一直等了你两个小时。 (可能表示不满)
I have waited for you for two
hours.
(6) 现在完成进行时强调动作,而现在完成时强调结果。
Who has been eating the
oranges?
Who has eaten the
oranges?
三、有些动词不能用于现在完成进行时,但可用于现在完成时
①表示状态的动词:be, have, exist等
②表示感情的动词:like, love等
③表示感觉的动词:see, hear, know等