Question

have，has，have been，has been在什么情况下用

Answer 1

1）have +过去分词,构成完成时态,例如：
He has left for London. 他已去了伦敦.
By the end of last month, they had finished half of their work.
上月未为止,他们已经完成工作的一半.
2）have + been +现在分词,构成完成进行时,例如：
I have been studying English for ten years.
我一直在学英语,已达十年之久.
3）have+been +过去分词,构成完成式被动语态,例如：
English has been taught in China for many years.
中国教英语已经多年.
由助动词 have(has)+动词的过去分词构成现在完成时.
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.