现在完成时
动词发生在过去,影响到现在,延续到现在,某种经历.
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（have/has+主语+过去分词+其他）
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 had no money to spend now.(现在我没有钱花了.)
Jane has laid the table.(简已经摆桌子.)
Michael has been ill.(现在仍然很虚弱)
He has returned from abroad. (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.
现在完成进行时
现在完成进行时的谓语动词构成.
I/ we/ you/ they have been working
he/ she/ it has been working
（一）表示从过去某时开始一直持续到现在的动作,并且还将持续下去.
The Chinese have been making paper for two thousand years.
中国有2000年的造纸历史.（动作还将继续下去）
I have been learning English since three years ago.
自从三年前以来我一直在学英语.（动作还将继续下去）
（二）表示在说话时刻之前刚刚结束的动作.
We have been waiting for you for half an hour.
我们已经等你半个钟头了.（动作不再继续下去）
（三）有些现在完成进行时的句子等同于现在完成时的句子.
They have been living in this city for ten years.
They have lived in this city for ten years.
他们在这个城市已经住了10年了.
I have been working here for five years.
I have worked here for five years.
我在这里已经工作两年了.
（四）大多数现在完成进行时的句子不等同于现在完成时的句子.
I have been writing a book.（动作还将继续下去）
我一直在写一本书.
I have written a book.（动作已经完成）
我已经写了一本书.
They have been building a bridge.
他们一直在造一座桥.
They have built a bridge.
他们造了一座桥.
（五）表示状态的动词不能用于现在完成进行时.
I have known him for years.
我认识他已经好几年了.
* I have been knowing...
这类不能用于现在完成进行时的动词还有：love爱,like喜欢,
hate讨厌,等.
现在完成时：
1）现在完成时为过去发生的,强调过去的事情对现在的影响,强调的是影响.
2）现在完成时通常与模糊的时间状语连用,或无时间状语.
共同的时间状语:
this morning, tonight,this April, now, once,before, already, recently,lately
现在完成时的时间状语
for, since, so far, ever, never, just, yet, till / until, up to now, in past years, always,
不确定的时间状语
3）现在完成时可表示持续到现在的动作或状态,动词一般是延续性的,如live, teach, learn, work, study, know.
现在完成进行时 :
其构成形式如下：
I / we / they have
He / she / it has been + 动词的现在分词
功用如下：
1） 表示一个在过去开始而在最近刚刚结束的行动,如：
Ann is very tired. She has been working hard.
Why are you clothes so dirty? What have you been doing?
2) 表示一个从过去开始但仍在进行的行动,如：
It has been raining for two hours. (现在还在下)
Jack hasn’t been feeling very well recently.
3) 表示一个从过去开始延续到现在,可以包括现在在内的一个阶段内,重复发生的行动,如：
She has been playing tennis since she was eight.
4) 现在完成时强调动作行为的结果、影响,而现在完成进行时只强调动作行为本身,如：
Tom’s hands are very dirty. He has been repairing the car.
The car is going again now. Tom has repaired it.
注意：
现在完成时有否定结构,而现在完成进行时没有否定结构.
现在完成时态可表示做完的时期以及已有的经验、但现在完成进行时不可以
现在完成时：强调对现在的影响
现在完成时进行时：强调过去那一段过程(对现在的影响)
现在完成时
I have done it.我已经做了
强调你做过的事情的本身,现在有否做不是关键
现在完成进行时
I have been doing it for years. 我已经做了几年了.
说明这个行动没有断过,现在还在做.
现在完成时,强调过去完成的动作对现在的影响.
例：-Would you like to have lunch with me ?
-I have had it.
意思是说我吃过,不能跟你一起去了.
现在完成进行时,强调动作的持续进行,现在动作还在进行.
例： I have been working in this factory for 5 years.
表示强调时间之久,目前还在那工作.
简单的来说,完成时态就是在过去发生的事情,做这件事情的动作在过去完结,而现在完成进行时则是做一个动作从过去一直延长到现在.