Question

谁能告诉我现在完成时的用法

Answer 1

现在完成时用法解析

1.构成

现在完成时是由助动词 have(has)+动词的过去分词构成。助动词说明该谓语是属于现在时范围。它和主语的人称、数要保持一致。过去分词是主要的谓语动词，说明句子的意义。

2.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.

你(已经)吃午饭了吗？ 我刚刚吃过。(现在我不饿了)

(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”，常带有twice,ever,never,three times等时间状语。

如： I have been to Beijing twice.我去过北京二次。

3.现在完成时的时间状语

(1)现在完成时属于现在时范围，故不能和过去的时间状语连用。如：yesterday,last Sunday,in1990,three years ago等。但是，在强调动作产生的后果和影响时，可以和一些表示不确定的时间状语连用。

a. 用副词already和yet。already一般用于肯定句中，yet一般用于否定句和 疑问句中。如：We have already finished our homework.我们已完成作业了。

They haven't finished their homework yet.他们还没有完成作业。

b.用ever 和never。多用于否定或疑问句中，表示“曾经”或“从未“等。 如：-Have you ever been to the Great Wall?你曾经去过长城吗？

-I have never been to the Great Wall.我从未去过长城。

c.用表示到说话为止的过去时间状语，如just,before,up to now,the past few years等。例如：I have seen her before,but I can not remember where.

我以前见过她，但记不起在哪里见过。

He has been there three times the last few days.

近几年他去过那里三次了。

d.用包括“现在”在内的时间状语，如：now,today,this morning(month,year,term)等。例如：-Have you met him today?-No,I haven't.

今天你见过他吗？我 没有。

How many times have you been there this year?

今年你去过那里多少次？

(2)现在完成时可以和带有since或for等表示“一段时间”的状语连用,表示动作或状态从某一时刻开始，一直持续到现在。如：I haven't seen him for two years. 但是，像come,arrive,buy等终止性动词不能与表示“一段时间”的状语连用。要用，必须改为“be(在)”等延续性动词来表述。现归纳总结一下由非延续性动词到延续性动词的转换：

arrive→be here begin(start)→be on

die →be dead come back→be back

leave →be away fall ill(sick,asleep)→be ill(sick,asleep)

get up→be up go out →be out

finish →be over put on →wear 或be on

open →be open join →be in或 be a member of…

close →be closed go to school→be a student

borrow →keep buy →have

catch(a cold)→ have(a cold) get to know →know

begin to study→study come to work→work等

如：He has been a soldier for three years.他参军三年了。

His father has been dead for two years.他父亲去世二年了。

The film has been on for ten minutes.电影已开始十分钟了。

We have studied English for three years. 我们(开始)学英语已三年了。

4.现在完成时和一般过去时的区别

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。试比较：

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)

5.几点注意事项

(1)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。

(2)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。

(3)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。

Answer 2

现在完成时
1.概念：过去发生或已经完成的动作对现在造成的影响或结果，或从过去已经开始，持续到现在的动作或状态。
2.时间状语：recently, lately, since…for…,in the past few years, etc.
3.基本结构：have/has + done
4.否定形式：have/has + not +done.
5.一般疑问句：have或has。
6.例句：I've written an article.
The countryside has changed a lot in the past few years.

Answer 3

Answer 4

Answer 5

编辑本段]句型
基本结构：主语+have/has+过去分词(done)
①肯定句：主语+have/has+过去分词+其他
②否定句：主语+have/has+not+过去分词+其他
③一般疑问句：Have/Has+主语+过去分词+其他
④特殊疑问句：特殊疑问词+一般疑问句
[编辑本段]过去分词
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 ”。
work---worked---worked ,visit---visited---visited
(2)、以“ e ”结尾的动词，只在词尾加“ d ”。
lived---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 ,
play---played---played ,stay---stayed---stayed
(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
2 、不规则动词：
AAA型
原型 过去式 过去分词
burst burst burst
cast cast cast
cost cost cost
cut cut cut
hit hit hit
hurt hurt hurt
put put put
set set set
shut shut shut
spread spread spread
let let let
AAB型
beat beat beaten
ABA型
become became become
run ran run
come came come
特殊情况
read read read
read原形发音为/ri:d/,过去式和过去分词发音为/red/
ABB型
bring brought brought
buy bought bought
build built built
burn burnt burnt
catch caught caught
dig dug dug
feel felt felt
fight fought fought
find found found
hear heard heard
hold held held
keep kept kept
lay laid laid
lead led led
lose lost lost
make made made
meet met met
sell sold sold
shoot shot shot
sit sat sat
stand stood stood
sweep swept swept
teach taught taught
tell told told
think thought thought
win won won
ABC型
begin began begun
blow blew blown
break broke broken
choose chose chosen
draw drew drawn
drive drove driven
drink drank drunk
fly flew flown
forgive forgave forgiven
forget forgot forgotten
freeze froze frozen
give gave given
grow grew grown
know knew known
ride rode ridden
rise rose risen
ring rang rung
shake shook shaken
sing sang sung
sink sank sunk
swim swam swum
throw threw thrown
write wrote written
[编辑本段]用法
（1）定义：现在完成时用来表示现在之前已发生过或完成的动作或状态,但其结果却和现在有联系,也就是说,动作或状态发生在过去但它的影响现在还存在.
I have no money to spend now.(含义是:现在我没有钱花了.)
Jane has laid the table.(含义是:简已经摆桌子.)
Michael has been ill.(含义是:现在仍然很虚弱)
He has returned from abroad. (含义是:现在已在此地)
（2）定义： 现在完成时可以用来表示发生在过去某一时刻的,持续到现在的情况,常与for,since连用.
Mary has been ill for three days.
I have lived here since 1998.
注意： 1.现在完成时不能单独与准确时间连用，
如yesterday(morning、afternoon),last(morning、afternoon)等，除非与for,since连用.
2.现在完成时往往同表示不确定的过去时间状语连用
,如already, yet, just, before, recently,still, lately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 ?
3. 现在完成时常常与表示频度的时间状语连用,
如often, sometimes, ever, never, twice, on several occasion等:
Have you ever been to Beijing
I have never heard Bunny say anything against her.
I have used this pen only three times. It is still good.
George has met that gentleman on several occasions.
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. 现在完成时表示现在之前业已完成的动作,虽然其效果或影响仍然存在但已不再继续,但是有一些现在完成时的句子,在后面加上for+一段时间,则现在完成时的动作就表示延续性.
Thomas has studied Russian. (现在不再学俄语)
Thomas has studied Russian for three years. (=Thomas began to study Russian three years ago, and is still studying it now.(同第2点用法第一个例句)
6. 现在完成时还可以用来表示过去的一个时间到现在这段时间内重复发生的动作.
We have had four texts this semester.
现在完成时的“完成用法”和“未完成用法”
1.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？
2.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：(1)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。
(2)现在完成时常见两种句型：
①for短语
②It is＋一段时间＋ since从句
3.一段时间+has passed+since从句
4.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
一.have/has been doing sth.
[编辑本段]for和since的运用
for表示及“经历（一段时间）”，而since表示“从……以来”。常见结构：
for+一段时间； since+一段时间+ago； since+一个时间点； since+从句
如：He has stayed here for 3 hours .他留在这儿已经有三个小时了。
He has stayed here since 3 hours ago.他三个小时前就已经留在这儿了。
He has stayed here since 3 o'clock. 他从三点钟一直留在这儿。
He has talled English since he came here .他到这以后就教英语。
1.现在完成进行时
当后面接有一段时间的词时,或是加表示时间的词时,可以用现在完成时.如果这件事现在还在持续或还在做,则可用
现在完成进行时.
如:I have been skating for 4 hours.
I have finished my homework.
2.现在完成时的被动语态.
后接动词的过去分词.
如:The building has been built for 5 years.
二.一般现在时:用动词原形
一般过去时:用动词的过去式
一般将来时:will/shall+do
is/am/are going to do
过去将来时:could/would do
现在完成时:have/has done
过去完成时:had done
将来完成时:shall have done
过去将来完成时:would/could have done
现在进行时:is/am/are doing
过去进行时:was/were doing
将来进行时:will/shall be doing
过去将来进行时:would/could be doing
现在完成进行时:have/has been doing
过去完成进行时:had been doing
将来完成进行时:shall have been doing
过去将来完成进行时:would have been doing
此时态一般在中学学习
[编辑本段]一般过去时和现在完成时
（ 1 ）、一般过去时的谓语动词用过去式，而现在完成时的谓语基本构成是“助动词 have/ has + 过去分词”。
(2) 、一般过去时通常与表示过去的时间状语连用。如： yesterday, last week , two years ago ,just now ,in 2002 等；而现在完成时则常与 just ,already ,ever ,never 等副词和 these days ,this week ,since ......, for ...... 等表示一段时间的状语连用。
试比较以下几组句子，有什么区别：
① A:Have you seen the film ?
B:Did you see the film ?
分析：你看过这部电影吗？（ A ）句强调的是被问者对剧情是否了解；（ B ）句强调的是看这部电影的动作是否发生过，并不强调是否知道其内容。
② A:How has he done it ?
B:How did he do it ?
分析：他是怎么做的这件事？（ A ）句强调的是他做着件事的方式对现在产生了某种影响；（ B ）句单纯的询问做这件事的方式。
③ A:He has lived in Beijing for 8 years .
B:He lived in Beijing for 8 years .
分析：他在北京住了 8 年。（ A ）句讲的是到目前为止他在北京住了 8 年，可能还会继续在北京住下去。（ B ）句讲的是他在北京住过 8 年，现在已经不在北京了。
（2）现在完成时强调过去发生的动作对现在的影响和结果，而一般过去时与现在没有联系，只是说明某个动作发生的时间是在过去。
比：I have washed the car. 我洗过了车。（看上去很漂亮）
I washed the car a moment ago. 我刚才洗过车了。
She has watered the flowers. 她已经浇了花。（不需要再浇了）
She watered the flowers yesterday. 她昨天浇的花。
I have written the letter but I haven't posted it yet. 信我已经写好了，但还没有寄出。
I wrote the letter last week and I posted it three days ago. 我上周写的那封信，3天前寄出的。
（3）现在完成时表示的动作或状态延续到现在并可能延续下去，而一般过去时则单纯表示过去某段时间内的经历。
比：It has rained for five hours. 雨已经下了5个小时了。
It rained for live hours yesterday. 昨天下了5个小时的雨。
He has waited for her for two hours. 他等她已经两个小时了。
He waited for her two hours and then went home. 他等她等了两个小时，然后就回家了。
I have reviewed two lessons this morning. 今天上午我已经复习了两课。（说话时还在上午）
I reviewed two lessons this morning. 今天上午我复习了两课。（说话时已是下午或晚上）

参考资料：http://baike.baidu.com/view/191047.html?wtp=tt