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初中三年级英语

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  • 填空题
    填入动词的适当形式。
    1. Can you imagine yourself ______ in a lonely island? (stay)
    2. I can't understand your ______ at that poor child. (laugh)
    3. She didn't mind _______ overtime. (work)
    4. To make a living, he tried ______, ______, and various other things, but he had failed in all. (write; paint)
    5. We are looking forward to Mary's _______ (come).
    6. She was praised for _______ the life of the child. (save)
    7. She ought to be praised instead of ______ (criticize).
    8. Is there any possibility of our ______ the championship? (win)
    9. He came to the party without ______ (invite)
    10. Don't keep me _______ (wait) for a long time.
    本题信息:2012年专项题英语填空题难度一般 来源:曾庆艳
  • 本题答案
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本试题 “填入动词的适当形式。1. Can you imagine yourself ______ in a lonely island? (stay)2. I can't understand your ______ at that poor child. (laugh)3. Sh...” 主要考查您对

被动语态

分词

动名词

现在完成时

等考点的理解。关于这些考点您可以点击下面的选项卡查看详细档案。
  • 被动语态
  • 分词
  • 动名词
  • 现在完成时
语态:
是动词的一种形式,它表示主语和谓语的关系。
语态有两种:主动语态和被动语态。
如果主语是动作的执行者,或者是说动作是由主语完成的,要用主动语态;
如果主语是动作的承受者,或者是说动作不是由主语而是由其他人完成的,则用被动语态。
被动语态的构成:
被动语态的基本结构:
主语+be +过去分词(+by+动作的发出者)
① 一般现在时:am/is/are+过去分词
如:Trees are planted every year.
② 现在进行时 am/is/are+ being +过去分词
如:The road is being repaired. 
③ 现在完成时 have/has + been +过去分词
如:The work has been finished.
④ 一般过去时 was/were + 过去分词
如:The story was told by him.
Many birds were killed last year.
⑤过去进行时 was/were+ being + 过去分词
如: The new house was being painted when I got home.
⑥过去完成时 had +been+ 过去分词
如: He told me that the work had been finished.
⑦一般将来时  will +be + 过去分词
如:The problem will be discussed tomorrow.
⑧ 过去将来时 would/should +be +过去分词
如: He said that the Christmas tree would be put up soon.
⑨情态动词的被动语态
情态动词+ be +过去分词    
如:The problem must be solved soon.
Children should be taught to love animals.
被动语态使用注意:
1. 不及物动词无被动语态。 如:happen, break down, come out......
What will happen in 100 years.
The dinosaurs disappeared about 65 million years ago.
2. 有些动词用主动形式表示被动意义。 如: write, sell, ride.....
This pen writes well.
This new book sells well.
3. 感官动词或使役动词使用省略to的动词不定式,主动语态中不带“to”,但变为被动语态时,须加上“to”。
例:make somebody do something→somebody+ be +made to do something
see somebody do something→somebody +be +seen to do something
A girl saw my wallet drop when she passed by.→My wallet was seen to drop by a girl when she passed by.
The boss made the little boy do heavy work.→The little boy was made to do heavy work by the boss.
4. 如果是接双宾语的动词改为被动语态时,直接宾语(物)作主语,那么动词后要用介词,这个介词是由与其搭配的动词决定。
He gave me a book.→A book was given to me by him.
He showed me a ticket.→A ticket was shown to me by him.
My father bought me a new bike. →A new bike was bought for me by my father.
5. 一些动词短语用于被动语态时,动词短语应当看作一个整体,而不能丢掉其中的介词或副词。
We can’t laugh at him. →He can’t be laughed at by us.
He listens to the radio every day. →The radio is listened to by him every day.
The nurse is taking care of the sick man. →The sick man is being taken care of by the nurse.
构成be+done.
主动句变为被动句所遵循的4个步骤:
①把原主动句中的宾语变为被动句的主语
②把动词变为被动形式即be +过去分词,并注意其人称和数随主语的变化,而动词的时态则保持不变。
③原主动句的主语如需要则放在by后面以它的宾格形式出现(注代词的宾格),如不需要则可省略。
④其它的成分(定语、状语)不变。

不用于被动语态的情形:
①不及物动词没有被动语态
这类动词有take place, happen, come about, break out, appear, disappear, last,  arise等。
例如:A fire broke out during the night.
②某些静态动词不用于被动语态
这类动词有have, lack, fit, hold, suit, resemble等。 
例如:My shoes do not fit me.
③宾语为相互代词和反身代词时不用于被动语态
例如:We should help each other.

关于主动形式表示被动意义:
①系动词(如look, sound, smell, feel, taste, prove等)要用主动表被动,因为系动词为不及物动词,它们没有被动语态形式。
例如:The building looks very beautiful.
②当open, close, shut, lock, move, read, wash, clean, cook, cut, wear, carry 等用作不及物动词且表示主语的某种属性时,通常用主动形式表示被动意义。
例如:The book sells well.
③有的动词本身含有被动意味,通常用主动形式来表示被动含义。
例如:Her eyes filled with tears.
④不定式to blame, to let用作表语时,通常要用主动表被动。
例如:Who is to blame?
⑤某些“be+形容词+to do”结构中的不定式通常要用主动形式表示被动意义。
例如:The book is difficult to understand.
⑥不定式用于某些动词(如have, have got, get, want, need等)的宾语后作定语时,如果不定式的逻辑主语就是句子的主语,通常用主动形式表示被动意义。
例如:Do you have time to help us?
⑦在too...to do sth.和...enough to do sth. 这两个结构中,若主语与其后不定式为to do sth.被动关系,则该不定式通常用主动形式表示被动意义(有时也可直接用 被动式)。
例如:The writing is too faint to read.
⑧be worth后的动名词要用主动表被动。
例如:This movie is worth seeing.
⑨在need, want, require等少数表示“需要”的动词后的动名词用主动形式表示被动意义。
例如:The house needs cleaning.

表示“据说”的三类被动句型:
①It is said that...句式
例如:It is said that thirteen is an unlucky number.
②There is said that...句式 
例如:There is said to be plenty of oil off our coast.
③sb./sth.is said that...句式
例如:Mr. Brown is said to have died of liver cancer.
被动语态各时态构成 :

时态

被动语态 

一般现在时

am/is/are+过去分词

一般过去时

was/were+过去分词

现在进行时

am/is/are being+过去分词

过去进行时

was/were being+过去分词

一般将来时

will be+过去分词

过去将来时

would be+过去分词

现在完成时

have/has been+过去分词

过去完成时

had been+过去分词

情态动词

情态动词be+过去分词


情态动词的被动语态:
一、理解含情态动词的被动语态的概念含情态动词的被动语态说明某个被动性动作所反映出的感情和态度。
初中阶段可用于被动语态的情态动词有“can、may、must、need、should”等,
分别表示“能够被……”,“可以被……”,“必须被……”,“需要被……“,应该被……”等。

二、掌握含情态动词的被动语态的不同句式的变换方法含情态动词的被动语态的疑问句、否定句的变化均借助于情态动词完成。
(一)一般疑问句直接将陈述句被动语态中的情态动词提前。如:
Mustthisworkbedoneatonce?这项工作必须立即完成吗?
Shouldyourhomeworkbefinishedbeforesix?你的家庭作业应在六点前完成吗?
(二)特殊疑问句由疑问词加上一般疑问句被动语态构成。如:
Whenmustthisworkbedone?这工作必须在什么时候完成?
Wherecanthelostbookbefound?这本失踪的书能在什么地方被找到?
(三)反意疑问句借助情态动词构成附加疑问部分。如:
Thisbridgecanbebuiltnextyear,can'tit?这座桥明年能建成,是吗?
Thisbookshouldn'tbetakenoutofthelibrary,shouldit?这本书不应被带出图书馆,是吗?
(四)否定句在情态动词后面加上“not”或“never”即可,但“must”表“必要”时否定式为“needn't”。如:
Thisworkneedn'tbedoneatonce.这项工作没必要立即做。Thisdustbinshouldn'tbeputhere.这个垃圾箱不应放在这儿。

三、含情态动词的被动语态的一般疑问句的回答含情态动词的被动语态的一般疑问句的回答应保留原情态动词,
但“must”表“必须”时,其否定回答应用“needn't”、“need”表“必要”时,其肯定回答应用“must”。如:
—Shouldmyexercisesbefinishedtoday?我的作业应在今天完成吗?
—Yes,theyshould.是的,应在今天完成。(No,theyshouldn't.不,不应在今天完成。)
—Musthisexercisebookbehandedinatonce?他的练习本必须立即上交吗?
—Yes,itmust.是的,必须立即上交。(No,itneedn't.不,不必立即上交。)
—Needhebeoperatedonatonce?他必须立即手术吗?
—Yes,hemust.是的,他必须。(No,heneedn't.不,他不必。)
分词:
就是具有动词及形容词二者特征的词;尤指以-ing或-ed,-d,-t,-en或-n结尾的英语动词性形容词,具有形容词功能,同时又表现各种动词性特点,
如时态,语态、带状语性修饰语的性能及带宾语的性能。
分词分为现在分词和过去分词两种,是一种非谓语动词形式。
现在分词和过去分词主要差别在于:
现在分词表示"主动和进行",过去分词表示"被动和完成"(不及物动词的过去分词不表示被动,只表示完成)。
分词可以有自己的状语、宾语或逻辑主语等。

现在分词构成形式:
①一般在动词原形末尾加ing,如do→doing、sing→singing、comfort→comforting
②以不发音的e、ue结尾的动词,先去e,再加ing,如dance→dancing、hike→hiking、write→writing、make→ making,take→taking
③以ee、oe、ye结尾的动词加ing,如see→seeing、toe→toeing、dye→dyeing
④以重读闭音节结尾的动词,并且末尾只有一个辅音字母,应双写这一字母,再加ing,如cut→cutting、swim→swimming
注:结尾是x则不必双写,如relax→relaxing
⑤以ie结尾的动词,要把ie变成y再加ing,如die→dying,lie→lying.
⑥以ic结尾的动词,要把ic变成ick再加ing,如picnic→picnicking,traffic→trafficking

过去分词构成形式:
1.规则动词:规则动词的过去分词的构成规则与规则动词的过去式的构成规则相同。四点变化规则:
(1)、一般动词,在词尾直接加“ ed ”。(然而要注意的是,过去分词并不是过去式)
work---worked---worked ,  visit---visited---visited
(2)、以不发音的“ e ” 结尾的动词,只在词尾加“ d ”。
live---lived---lived
(3)、以“辅音字母 + y ”结尾的动词,将 "y" 变为 "i" ,再加“ ed ”。
study---studied---studied,cry---cried---cried,try---tried---tried,fry---fried---fried.[1]
(4)、重读闭音节结尾,末尾只有一个辅音字母,先双写该辅音字母,再加“ ed ”。
stop---stopped---stopped  ,  drop---dropped--dropped
(5)、以ic结尾的动词,要把ic变成ick再加ed,
picnic→picnicked  ,traffic→trafficked
2 、不规则动词:见不规则动词表


分词用法:
1、分词作状语   
分词在句子中作状语,可以表示时间、条件、原因、结果、让步、伴随等。   
分词(短语)作状语时,其逻辑主语应与句中主语相一致。
当现在分词表示的动作发 生在谓语动词之前时, 则用现在分词的完成式,且所表示动作与谓语动作同时发生, 则用现在分词的一般式。
完成或被动关系用过去分词。   
①现在分词:
The students went out of the classroom, laughing and talking.   
②过去分词:
Accompanied by his friend, he went to the railway station. 
Given   better attention, the plants could grow better.   

2、“while ( when, once, until, if , though等连词)+分词”结构   
现在分词或过去分词作状语时,有时可以在分词前加while,when, once, although, until, if等连词。   
①现在分词:
When leaving the airport, she waved again and again to us.
While waiting for  the train, I had a long talk with my sister about her work……   
②过去分词:
Once recovered, he threw himself into his work and made every effort to do it  well.   
Although working very hard, he failed to pass the final exam. If translated word by word, the passage will be difficult to understand.   

3、分词作定语   
分词作定语时,单个的分词通常放在被修饰的名词之前,分词短语一般置于所修饰的中心词后面。
现在分词修饰的是发出该动作的名词(即与名词有主谓关系),过去分词修饰承受该动作的名词(即与名词是动宾关系)。    
We will go on with our experiment as soon as we get the added fund.    
This is really an exhausting day to all of us!   
We can see the part of the moon lighted by sunlight.   
After a night spent in excitement and sleeplessness, I forced myself to take a long walk along the beach the next day.   
More and more developing countries established strategic partnership with  developed countries   

4、分词作宾语补足语   
现在分词在see, watch, hear, observe, notice, feel, find, glimpse, glance等感官动词和look at, listen to等短语动词以及
have, keep, get, catch, leave, set, start, send等使役动词后面与名词或代词构成复合宾语,作宾语补语的成分。
例:I see him passing my house every day.
I caught him stealing things in that shop.
I smelt something burning.

5、分词作表语
分词作表语通常看作形容词来用。
过去分词表示主语的感受或状态,主语多为人。现在分词表示主语的性质,而且主语多为物;
①过去分词:
We were so bored that we couldn’t help yawning.
She felt confused, and even frightened.
②现在分词:
He was very amusing.
That book was rather boring.
很多动词的现在分词都可以作表语:
exciting, interesting, encouraging, disappointing, confusing, touching, puzzling.


动名词:
如果一个动词加上了ing变成了名词,那么这个词称动名词。 动名词是一种兼有动词和名词特征的非限定动词。
它可以支配宾语,也能被副词修饰。
由于动名词是由动词变化而来,它仍保留着动词的某些特征,具有动词的某些变化形式,用以表达名词所不能表达的较为复杂的意念。
动名词的名词特征表现在它可在句子中当名词来用,作主语、宾语、表语、定语。

动名词的结构和形式:
动名词的否定结构:
动名词的否定结构由not 动名词组成。如:
Trying without success is better than not trying at all. 实验没有成功也比不实验好。
He hated himself for not having work hard. 他悔恨自己没有用功。
I’m sorry for not having telephoned you before. 很抱歉,没有早给你打电话。
He felt sorry for not having done the work well. 他为没有把工作做好感到难过。
I fancy it has done you a lot of good not going. 我看不去对你倒好了。
(not going 是动名词一般式的否定形式)
There is no denying the fact that he si diligent.
(no denying 也是动名词一般式的否定)

动名词复合结构:
通常情况下,动名词的逻辑主语为谓语动词的主语。如果动名词动作的发出者不失谓语动的主语时,则需要有自己的逻辑主语物主代词或名词所有格加动名词就构成了动名词的复合结构,这种结构在句中可以作主语,宾语等。
(1)逻辑主语是有生命的名词作主语时,必须用名词或代词所有格,作宾语时(尤其在口语中),也可用名词普通个或人称代词宾格。如:
Do you think my going there will be of any help?
你看我去会有什么帮助吗?(宾语)
The student’s knowing English well helps him in learning French.
这位学生通晓英语对他学法语很有帮助。(主语)
Do you mind my(me) smoking ? 你介意我抽烟吗?(宾语)
They insist on Mary’s (Mary) going with them there.
他们坚持要玛丽跟他们一起去那儿。(介词宾语)
(2)逻辑主语是无生命名词是,通常只用名词普通格。如:
Do you hear the rain pattering on the roof?
你听见雨点打在屋顶上了吗?
Is there any hope of our team winning the match ?
我们对赢得比赛有希望吗?
(3) 逻辑主语是指示代词或不定代词this that , somebody , someone , nobody, none, anybody, anyone 时,只用普通格。如:
She was woken up by somebody shouting outside.
她被外面喊叫的人吵醒了。

动名词的形式(一般式,完成式和被动式):
(1) 动名词的一般式所表示的动作与谓语动词所表示的动作同时发生,或在谓语动词表示的动作之后。如:
We are very interested in collecting stamps. 我们对集邮很感兴趣。
His coming will be of great help to us . 他来对我们大有帮助。
但是有些明确表示时间的动词和介词 after, on,upon, 或for之后,常用一般式代替完成式,表示动作发生在谓语动作之前。如:
I shall never forget seeing the Great Wall for the first time.我永远不会忘记第一次看到长城的情景。
On hearing that bad news , the mother couldn’t help crying. 一听到这个糟糕的消息,母亲就禁不住哭了起来。
Excuse me for coming late. 我来晚了,请原谅。
Thank you for giving us so much help. 谢谢你给了我们这么多帮助。
(2) 动名词的完成式所表示的动作或状态在谓语动词之前完成或结束。
He regrets not having taken part in the work. 他后悔没有参加这项工作。
We were praised for having finished the work ahead of time. 我们因提前完成了这项工作而受到了表扬。
(3)动名词的被动式:当动名词的逻辑主语是行为承受者时,用被动语态。如:
I like being given harder work. 我喜欢接受难点的工作。
She is proud of being admitted into the university. 她为被大学录取而感到自豪。
The meeting was put off without his having been consulted. 会议延期并未和他商量。
He doesn’t mind having been criticized. 他不介意过去受到的批评。


动名词与现在分词的关系:
动名词它在形式上与现在分词相同,都是在动词原形的词末加-ing。在现代语法中,这两种形式同视为"-ing形式"。
这两种形式的另一个相同之处是:
它们都是由动词变化而成的,它们都保留了动词的某些特征,它们都能带自己的宾语、状语,而构成动名词短语或是现在分词短语去担当句子成分。
例如:
Speaking in the public,he will surely be very cheerful .
(现在分词短语,作状语)他在公众场所讲话时总是兴高采烈的。
She hates speaking in the public.
(动名词短语,作宾语)她不喜欢在公众场所讲话。

动名词和现在分词都可以用于系动词之后作表语,区别方法是:
①作表语的动名词与主语指的是同一件事,此时系动词相当于“是”,通常把主语和表语的位置互换,语法和意思不变,例如:
My hobby is swimming.可改为Swimming is my hobby.(可将原句中的主语与表语位置互换)
②现在分词作表语主要用以说明主语的性质,不能与主语互换位置,例如:
The story is interesting .不可改为:Interesting is the story.
2.动名词和现在分词都可以用作定语来修饰名词,两者的区别在于:
动名词修饰名词时主要表示该名词的用途,而现在分词修饰名词时性质、状态或动作等。试比较:
①a swimming boy和a swimming suit
前者的意思是“一个正在游泳的男孩”,即a boy who is swimming,现在分词swimming 表示被修饰名词boy的动作;
而后者的意思是“游泳衣”,即a suit for swimming,动名词swimming表示suit 的用途。
②a sleeping child 和 a sleeping car
前者的意思是“一个正在睡觉的孩子”,即a child who is sleeping,现在分词sleeping 表示被修饰名词 child 正处于的状态;
而后者的意思是“卧车(被用来睡觉的车厢)”,即 a car which is used for sleeping,动名词 sleeping 表示car 的用途。


动名词用法口诀:
动名词常泛指,句法作用宾/表/定与主,时态/语态之形式,一般/完成/被动式。
Being done 系被动,不含任何进行意。用作主语请留意,常用it作形式主语,不指未来发生事,表达的信息系已知。
用作表语请记清,作用相当一名词,检验方法很简单,主与表换位能成立。
用作定语也易辩,表示名词之用途。
用作宾语稍复杂,关键留意谓语动词(跟动名词作宾语的常用动词附后),时态同谓动作比较,先于谓动用完成式,其逻辑主语不固定,在句中/句外均有之。
否定式其前加not,复合式其前加物主词,非句首宾格词也可用,尤其口语中更如此。
说明:1、主-----主语 2、宾-----宾语 3、表------表语 4、定------定语 5、谓动---谓语动词

动名词的用法:
一、动名词作主语 
1. 直接位于句首做主语。例如:   
     Swimming is a good sport in summer.   
2. 用 it 作形式主语,把动名词(真实主语)置于句尾作后置主语。   
动名词做主语时,不太常用 it 作先行主语,多见于某些形容词及名词之后。例如:
It is no use telling him not to worry.   
常见的能用于这种结构的形容词还有:better,wonderful,enjoyable,interesting,foolish,difficult,useless,senseless,worthwhile,等。   
注意:important,essential,necessary 等形容词不能用于上述结构。   
3. 用于“There be”结构中。例如:   
There is no saying when he'll come.很难说他何时回来。    
4. 用于布告形式的省略结构中。例如:   
No smoking ( =No smoking is allowed (here) ). (禁止吸烟)   
No parking. (禁止停车)   
5. 动名词的复合结构作主语   
当动名词有自己的逻辑主语时,常可以在前面加上一个名词或代词的所有格,构成动名词的复合结构
(这时,名词或代词的所有格做动名词的逻辑主语)。
动名词的复合结构也可以在句中作主语。例如:    
Their coming to help was a great encouragement to us.   

二、动名词作宾语
1.作动词的宾语   
某些动词后出现非限定性动词时只能用动名词作宾语,不能用不定式。常见的此类动词有:
admit, appreciate, excuse, stand, advise, allow, permit, avoid,  consider, enjoy, finish     
They went on walking and never stopped talking.他们继续走,说个不停。 
I found it pleasant walking along the seashore.在海滩上走真是乐事。   
Mark often attempts to escape being fined whenever he breaks traffic  regulations.   
每当马克违反交通规则时,他常常企图逃避罚款的处分。    
2.作介词的宾语   
We are thinking of making a new plan for the next term. 我们正考虑为下学期制定新的计划。   
Shall we have a rest or get down to doing our work? 我们休息呢还是开始干活?   
3.作形容词的宾语   
The music is well worth listening to more than once.  这种曲子很值得多听几遍。   
We are busy preparing for the coming sports meet. 我们正为马上到来的运动会忙着做准备。

三、动名词作表语
动名词作表语时句子主语常是表示无生命的事物的名词或what引导的名词性从句。
表语、动名词与主语通常是对等的关系,表示主语的内容,主语、表语可互换位置。   
Your task is cleaning the windows.   你的任务就是擦窗户。
(Cleaning the windows is your task.)   
What I hate most is being laughed at.  我最痛恨的就是被别人嘲笑。
(Being laughed at is what I hate most.)

四、动名词作定语
动名词作定语往往表示被修饰词的某种用途。如:   
a walking stick =a stick for walking=a stick which is used for walking   
a washing machine=a machine for washing=a machine which is used for washing    
a reading room=a room for reading=a room which is used for reading   
a measuring tape=a tape for measuring=a tape which is used for measuring   
sleeping pills=pills for sleeping=pills which is used for sleeping


动名词是非限定动词的一种形式,由动词原形+ing构成。它既有动词的特征,又有名词的特征,故称。
动名词也有时态和语态的变化,如表所示(以及物动词write为例),不及物动词没有语态的变化。
时态、语态 主动 被动
一般式 writing being  written
完成式
having written
having been written

动名词使用注意事项:
1) 动名词做主语时,谓语动词为单数
2) 在动名词和不定式中,作为介词的宾语是动名词
3) 动名词的否定直接在其前加否定词,通过代词的宾格或所有格形式给出逻辑主语
例:I would appreciate you calling back this afternoon.
4) 有些词后只能接动名词
acknowledge;admit; advise;advocate;allow;appreciate; avoid; celebrate; consider; contemplate; defer; delay; deny;
detest; discontinue; dislike; dispute; enjoy; it entails; escape; excuse; explain; fancy; feel like; finish; forgive; can’t help;
hinder; imagine; it involves; keep; it means; mention; mind; miss; it necessitates; pardon; postpone; practice; prevent;
recall; report; resent; resist; risk; suggest; understand...
5) 另外还有一些接-ing形式的常用说法
it’s no good; it’s no/little/hardly any/ use; it’s not/hardly/scarcely use; it’s worthwhile; spend money/time; there’s no;
there’s no point in; there’s nothing worse than; what’s the use/point
6) 有些词后面加不定式和动名词均可
remember,forget,try,stop,go on,continue,stop,regret,cease,mean后面均可用不定式和-ing形式,但意义截然不容。
例:remember to do/doing:
①I remembered to post the letters.(指未来/过去未来将要做的动作)
②I remembered posting/having posted the letters.(我记得做过这个动作)
 forget与remember的用法类似。
 regret的用法:
①I regret to inform you that…(我很遗憾地通知你……)
②I regretted having left the firm after twenty years.(为了“二十年前的离开”而遗憾。)
 try to(努力)与try +–ing(试验):
①You really must try to overcome your shyness.
②Try practicing five hours a day.
现在完成时:
过去发生并且已经完成的动作对现在造成影响或后果,过去某一时间开始并一直持续到现在的动作或状态。
基本结构:主语+have/has+动词的过去分词
句式:
1. 否定句式:现在完成时的否定句式是“haven't (hasn't)+过去分词...”。
如:I have not seen the movie yet. 我还没看这部电影。
2. 一般疑问句:Have(Has)+主语+过去分词...? 如:
—Have you finished the work?你已经做完这项工作了吗?
—Yes, I have. 是的,我已经做完了。(No, I haven't. 不,我还没有做完。)
3. 特殊疑问句:特殊疑问词+have(has)+主语+过去分词...?如:
How many times have you been to the Great Wall?你去过长城几次?
提示:肯定句中有some, already时,改为否定句或疑问句时通常要分别改为any, yet。如:
I have already finished my homework. 我已经完成了我的作业。
→ I haven't finished my homework yet. (否定句)
→ Have you finished your homework yet? (一般疑问句)
现在完成时常见两种句型:
①for短语
②It is+一段时间+ since从句
现在完成时特点:
1. 非持续性动词的完成时的肯定式不能与时间段连用,若要用时间段状语,则应换成相应的持续性动词或状态动词。
例如:
He has left.
He has been away for an hour.
2. have/has been to 表示曾经去过某地,但现在不在那;have/has gone to表示现在已去某地,现在不在这。
例如:
He has been to Canada, but now he is working in our company.
Mr. Li in not at home. He has gone to Shanghai.
3. 完成时的肯定式常用already,而否定式和疑问式常用yet,但若already用于疑问句时,表示一种出乎意外的惊讶。
例如:Have you read it already?
现在完成时和一般过去时区别:
现在完成时和一般过去时都表示在过去完成的动作。
但现在完成时强调的是这一动作与现在的关系。如对现在产生的结果或影响等,
而一般过去时只表示动作在过去某一时刻发生,不表示和现在的关系。
比较:
I have lost my new book.  我把新书丢了。(现在还未找到)
I lost my new book yesterday. 我昨天把新书丢了。(昨天丢的,现在找到与否没说明)

have been(to)与have gone( to)的区别:
have been(to)表示“去过某地(现在已经回来了)”,可用于各人称;
have gone(to)表示“去某地了(说话时某人不在当地)”,常用于第三人称,
前者可与once ,never,several times等连用,后者则不能。
如:
They have been to Beijing twice.他们去过北京两次。
He has gone to Beijing .  他去北京了。

现在完成时注意事项:
1.如单纯表示一段时间,或强调一段时间,虽有since一词,也不必用完成时。如:
It is two years since his father died. =His father has been dead for two years.他父亲去世已有三年了。

2.终止性动词现在完成时的否定式,已变成一种可以延续的状态,因此可以和表示一段时间的状语连用。如:
I haven't left here since 1997.自从1997年以来,我一直没有离开过这儿。

3..现在完成时不能单独与准确时间连用,(如表示过去的时间状语)
如:yesterday(morning、afternoon),last(morning、afternoon)等,除非与for,since连用.

4.不能与when连用.

现在完成时的用法:
1.表示动作发生在过去某个不确定的时间,但对现在留下了某种影响和结果。常被just、already、yet 等副词修饰。如:
-Have you had lunch yet?    
-Yes,I have. I've just had it.
2.表示从过去某一时刻开始一直持续到现在的动作或状态。这个动作可能刚停止,可能仍然在进行。
常带有for和since等表示一段时间的状语。如:
He has taught here since 1981
他自1981年就在这儿教书。(可能还要继续教)
I have't seen her for four years.
我有四年没见到她了。
3.表示说话前发生过一次或多次的动作,现在成为一种经验,一般译为汉语“过”。
常与twice,ever,never,three times等时间状语。 如:
I have been to Beijing twice.我去过北京

4. 现在完成时还往往可以同包括现在时间在内的时间状语连用,如:
now,up to these few days/weeks/months/years,this morning/week/month/year,just,today,up to present,so far等:
Peter has written six papers so far.
Man has now learned to release energy from the nucleus of the atom.
There has been too much rain in San Francisco this year.
The friendly relations and cooperation between our two countries have been enhanced in the past few years.
Up to the present everything has been successful.

5.现在完成时往往同表示不确定的过去时间状语连用,如:
already(肯定),yet(否定,疑问),just,before,recently,still,lately,never等:
He has already obtained a scholarship.
I haven't seen much of him recently (lately).
We have seen that film before.
Have they found the missing child yet?

6.现在完成时的"完成用法"
现在完成时的"完成用法"指的是动作发生在过去某一时刻并已结束,但该动作对现在产生了影响,与现在情况具有因果关系。
例如:
He has turned off the light.他已把灯关了。(动作结束于过去,但说明的是现在的情况--灯现在不亮了。)
现在完成时"完成用法"的特点是动作不延续,因此:
该时态只能与表示不定的过去时间状语(如:already,yet,before,recently等)、频度时间状语(如:never,ever,once等)、包括现在时刻在内的时间状语(如:this morning / month /year...,today等)连用。
例如:Have you found your pen yet?你已找到你的钢笔了吗?
7.现在完成时的"未完成用法"
现在完成时的"未完成用法"指的是动作开始于过去某一时刻,一直延续到现在,或可能还要继续下去。
例如:
He has lived here since 1978.自从1978年以来,他一直住在这儿。
(动作起始于1978年,一直住到现在,可能还要继续住下去。)
I have been in the army for more than 5 years.我在部队已经呆了五年多了。
(动作开始于5年前,一直延续至今,有可能还要继续下去。)
此种用法的句中常需一个表示一段时间的状语(由since或for引导),或表示与现在时刻相连的时间状语(如:up to now,so far)等。
例如:
I have heard nothing from him up to now.到目前为止我没有他的任何消息。
注意:现在完成时的未完成用法只适用于延续性动词,不可用于终止性动词,即瞬间完成或延续时间很短的动词。
如:come,go,arrive,leave,join,become,die等。
8.一段时间+has passed+since从句
主语+have / has been+since短语
例如:He has been in the League for three years.
或It is three years since he joined the League. 他入团已三年了  
9. 现在完成时常和短语 "up to now /till now","so far" (意思是从过去某一确定的时间一直延续到现在)连用。  
Up to/till now he's read many story books. 至今他已读过好多故事书。
I've been to New York three times so far. 至今我已到纽约去过三次。
has gone (to),has been (to),has been (in) 的区别
has gone to:去了没回
has been to :去过
has been in:呆了很久