区分have done和have been doing,我们需要从两个方面来讨论：
桃子的营养价值一、完成时态和完成进行时态本身意义的差别；
二、要结合动词的不同延续特点.首先我们来看两种时态的意义差别
两者根本区别是：完成进行时强调动作持续的过程(emphasis on duration),完成时强调动作的结果或成就(emphasis on achievement).具体来讲,现在完成进行时have been doing强调的是在一段时期内某项活动的持续性,强调的是动作本身.现在完成时have done则是强调动作产生的结果或取得的成就,而不是动作本身.二者的这种区别我们从下面的这些例句可以很好地领悟到： (2) a. My hands are very dirty. I’ve been painting the house. b. I have painted the house green. The house was white, but now it’s green.
思维分析：
句a中have been painting表示painting动作一直在持续,活动还没有结束,所以才有my hands are very dirty这样的现状.句a意思是“我的手很脏,我现在一直在给房间刷漆”.
lol啥意思句b中have painted表示painted动作已经结束,而且动作导致的结果是the house was white, but now it’s green房间现在是绿的了.
现在完成时表示动作业已完成, 而完成进行时却不一定如此
I’ve made a cake. 我做了一个蛋糕.（已做好）
I’ve been making a cake. 我一直在做一个蛋糕. （不一定做好了
大会主题She’s painted a picture. 她画了一幅画.（已画好）
圆的面积课件She’s been painting a picture. 她在画一幅画.（可能还没画好）
强调时间长度用完成进行时比较好： I’ve been coughing all night. 我咳了一整夜.（比I’ve coughed all night. 更能强调咳得久）
All the time she’s been sitting there in silence. 她一直静坐在那里.
All these years we’ve been trying to get in touch with him. 这些年来我们一直在设法和他联系.
许多静态动词都只能用于完成时而不能用于完成进行时：
I’ve known that for a long time. 这事我已经知道很久了.
The strike has lasted six months. 这次罢工已经持续了6个月.
Nobody has seen him since last week. 从上周起就没人见到过他.
raise in salary all the time. 他一直盼着加薪.
但当意思发生转变时也可能用于完成进行时：
I’ve been thinking of doing so for a long time. 我好久以来一直想这样做
.Tom has been seeing about a work permit for you. 汤姆一直在设法帮你取得工作许可证.
有少数动词用两种时态都可以,意思差别不大,如：
They have been working very well this term. 这学期他们学习很好. They have worked very well this term.
It has been raining for two hours. 下了两个小时的雨. It has rained for two hours.
过去完成时
一、过去完成时的概念与结构特点
概念：过去完成时表示在过去某一时间或动作之前已经发生或完成了的动作，即“过去的过去（ past-in-the-past ）”。
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非主流男头像图片那时以前 那时 现在
构成：过去完成时由“助动词 had + 过去分词”构成，其中 had 通用于各种人称。 They had already had breakfast before they arrived at the hotel. She had finished writing the composition by 10 ：00 this morning.
二、过去完成时的判断依据
1. 由时间状语来判定
一般说来，各种时态都有特定的时间状语。与过去完成时连用的时间状语有： （ 1 ） by + 过去的时间点。
如： I had finished reading the novel by nine o'clock last night.
（ 2 ） by the end of + 过去的时间点。
如： We had learned over two thousand English words by the end of last term.
（ 3 ） before + 过去的时间点。
如： They had planted six hundred trees before last Wednesday. 2. 由“过去的过去”来判定。
过去完成时表示“过去的过去”，是指过去某一动作之前已经发生或完成的动作，即动作有先后关系，动作在前的用过去完成时，在后的用一般过去时。这种用法常出现在： （ 1 ）宾语从句中
当宾语从句的主句为一般过去时，且从句的动作先于主句的动作时，从句要用过去完成时。在told, said, knew, heard, thought等动词后的宾语从句。如： She said that she had seen the film before. （ 2 ）状语从句中
在时间、条件、原因、方式等状语从句中，主、从句的动作发生有先后关系，动作在前的，要用过去完成时，动作在后的要用一般过去时。如：
When I got to the station, the train had already left.
After he had finished his homework, he went to bed.
注意： before, after 引导的时间状语从句中，由于 before 和 after 本身已表达了动作的先后关系，若主、从句表示的动作紧密相连，则主、从句都用一般过去时。如： Where did you study before you came here?
After he closed the door, he left the classroom.
（ 3 ）表示意向的动词，如hope, wish, expect, think, intend, mean, suppose等，用过去完成时表示"原本„，未能„"
We had hoped that you would come, but you didn't. 3. 根据上、下文来判定。
I met Wang Tao in the street yesterday. We hadn't seen each other since he went to Beijing.
三、过去完成时的主要用法
1. 过去完成时表示一个动作或状态在过去某一时间或动作之前已经完成或结束，即发生在“过去的过去”。如：
When I woke up, it had stopped raining.
我醒来时，雨已经停了。（主句的动作发生在“过去的过去”）
2. 过去完成时是一个相对的时态，表示的是“过去的过去”，只有和过去某一时间或某一动作相比较时才使用它。如：
清洁工职责 He told me that he had written a new book. (had written 发生在 told 之前 )
3. 过去完成时需要与一个表示过去的时间状语连用，它不能离开过去时间而独立存在。此时多与 already ， yet ， still ， just ， before ， never 等时间副词及 by ， before ， until 等引导的短语或从句连用。
如：Before she came to China, Grace had taught English in a middle school for about five years. Peter had collected more than 300 Chinese stamps by the time he was ten.
4. 过去完成时表示某一动作或状态在过去某时之前已经开始，一直延续到这一过去时间，而且动作尚未结束，仍然有继续下去的可能。
如： By the end of last year, he had worked in the factory for twenty years. （ had worked 已有了 20 年，还有继续进行下去的可能）
5. 过去完成时也用于（刚„就„）, no& （刚„就„）, It was the first time + that等一些固定句型中。
He had no sooner left the room than they began to talk about him. 他刚离开房间，他们就
议论起他来。 We had hardly begun when we were told to stop.
我们刚开始就被叫停。
It was the first time that he had ever spoken to me in such a tune.他用这样的语调跟我讲话，这是第一次。
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