内容正文:
Section Ⅲ Grammar——完成时
观察下列教材原句并思考黑体部分的功能
①Natural cloning has been going on for generations.
②Gardeners have been using a form of cloning when they take a cutting from a plant…
③For years, there had been attempts to clone animals artificially.
④…cloning primates has been proved to be “much harder”, and doing so with non-reproductive cells…
⑤Dr.Sun Qiang, director of the research team, said they had been wholly devoted to the research…
⑥…and had been taking care of more than 1,000 monkeys 24 hours a day, 7 days a week…
[语法感知]
1.句①②中黑体部分为 现在完成进行时 ,句④为现在完成时的 被动语态 。
2.句③⑤中黑体部分为 过去完成时 ,句⑥为 过去完成进行时 。
一、现在完成时
1.构成和意义:have/has+done,表示过去所发生的动作或事情对现在造成的影响或结果。
2.用法
(1)表示发生在过去的动作或存在的状态到说话时刚刚完成或结束。现在完成时常与up to now, so far, already, yet, now, recently, in the past few years, just等表示时间的词连用。
►In the past few years, great changes have taken place in my hometown.
在过去的几年里,我的家乡发生了巨大变化。
(2)下列情况下常用现在完成时:
①It is/has been+一段时间+since从句
②This/That/It is the first/second/…time that+现在完成时
③It/This is the best/worst/most interesting等+名词+从句+现在完成时
►It is/has been twenty years since I last saw her.
我已经二十年没见她了。
►This is the first time that we have seen a film in the cinema as a family.
这是我们全家第一次到电影院看电影。
►This is the most interesting novel he has ever written.这是他写得最有趣的一部小说。
在条件、时间或让步状语从句中,表示将来某时之前已完成的动作。
►When you have learned English, you will find it a bridge to so much knowledge.
当你学习英语之后,你将找到一条通往丰富知识的桥梁。
[即时训练1]——用所给动词的适当形式填空
(1)—I remember you were a talented pianist at college.Can you play the piano for me?
—Sorry, I haven't played (not, play) the piano for years.
(2)—Look! Somebody has cleaned (clean) the sofa.
—Well, it wasn't me.I didn't do it.
(3)This is the first time the company has ventured (venture) into movie production.
(4)In order to find the missing child, villagers have done (do) all they can over the past five hours.
(5)Recently, the CCTV and some TVs have begun (begin) to take some measures.
二、现在完成进行时
1.构成和意义:have/has+been+doing,现在完成进行时表示动作从过去某一时间开始,一直持续到现在,可能还要继续进行下去。
2.用法
(1)表示过去某一时刻发生的动作一直持续到现在,并有可能继续持续下去。
►He has been playing computer games all day.
他一整天都在玩电脑游戏。
►I have been working for this company for three years.
我在这个公司已工作三年了。
(2)表示一直到说话时为止的一段时间内一再重复发生的动作。
►The teacher has been telling us to be careful all the term.
这个学期,老师一直在告诉我们要细心。
(3)表达较重的感情色彩。
►You have been daydreaming but never make an effort.
你一直在做白日梦,但从不努力。
[即时训练2]
(1)补全句子
①Tom has been working hard (一直在努力学习) since the new term began.
②I have been playing football (一直在踢足球) all the morning, so I'm sweating heavily.
(2)用所给动词的适当形式填空
①I have been working (work) in this school since I graduated from college.Now I am still working here.
②You know, I have been looking (look) for a job for three months, and this is my first formal interview.
③The little boy is dirty all over because he has been playing/has played (play) in the mud all the morning.
三、现在完成进行时和现在完成时的区别
1.现在完成进行时强调动作的延续性;而现在完成时强调的是某个刚刚完成的动作,或某个过去的动作对现在的影响或产生的结果。
►I have been thinking it over.
我一直在仔细考虑。(延续性)
►I have thought it over.
我已经仔细考虑过这件事了。
2.现在完成进行时可以表示动作的反复性;现在完成时一般不表示动作的反复性。
►Have you been meeting him recently?
你最近经常见到他吗?(反复性)
►Have you met him recently?
你最近见过他吗?
3.现在完成进行时有时含有某种感情色彩;现在完成时一般表示平铺直叙。
►I have been waiting for you for two hours.
我一直等了你两个小时。(表示不满)
►I have waited for you for two hours.
我已经等了你两个小时。
[即时训练3]——补全句子
(1)He has developed a good habit (养成了一个好习惯) of independent learning.No wonder he ranks first in every exam in his class.
(2)Now that Lucy is out of work, she has been considering going back (一直考虑回去) to school, but she hasn't decided (未决定) yet.
四、过去完成时
1.构成和意义:had+done,过去完成时的基本用法与现在完成时相似,所不同的是:现在完成时的动作需在现在以前完成,过去完成时的动作需在过去某一时间以前完成,也就是说动作发生在“过去的过去”。
2.用法
(1)表示在过去某个时间或动作之前就已经发生的动作,通常简称为“过去的过去”。句中常有by, by the end of等介词(短语)和by the time, before, when, until等引导的状语从句。
►—Did you have difficulty finding Ann's house?
—Not really.She had given us clear directions and we were able to find it easily.
——你们找到安的家有困难吗?
——算不上难。她已经给了我们她家的具体的位置,我们能够容易地找到它。
►By the end of 2020, he had collected more than a thousand foreign stamps.到2020年底,他已经收集了1 000多枚外国邮票。
(2)过去完成时表示发生在过去某个动作或时刻之前的动作一直延续到过去的另一个时间,常与for, since等词连用。
►I had been at the bus stop for 20 minutes when a bus finally came.
公交车来时,我在车站已经等了20分钟。
(3)过去完成时在几个重点句型中的应用
①在no sooner…than, hardly…when句型中,主句用过去完成时,从句用一般过去时。意为“一……就;刚……就”。
►I had hardly stepped into the classroom when the bell rang.
我一踏入教室,铃就响了。
►No sooner had I reached home than it began to rain.我刚到家就开始下雨了。
②在“It was the first/second/…time that…”句型中,that从句的谓语动词用过去完成时。
►It was the first time that I had chatted online in English.那是我第一次用英语在网上聊天。
③It was+一段时间+since从句(从句用过去完成时)
►It was at least three months since I had left Beijing.我离开北京至少有3个月了。
④主句(过去完成时)+by the time+表示过去的从句
►By the time I got to the station, the train had already gone.
我到车站时,火车已经开走了。
⑤表示“意愿、打算”的动词,如hope, mean, want, think, expect, plan, intend等的过去完成时表示“原本……(但事实上并没有……)”之意。
►I had hoped to be back last night, but I didn't catch the train.
我本来希望昨天晚上回来的,但我没赶上火车。
[即时训练4]——单句语法填空
(1)Helen had left (leave) her keys in the office so she had to wait until her husband came home.
(2)By the time I left the school, he had taught (teach) the class for 3 years.
(3)She asked me whether I had returned (return) the books to the library, and I admitted that I hadn't.
(4)—Did you have to do much for the dinner party?
—Helen had finished (finish) everything by the time I got home.
(5)It was the second time that he had rushed (rush) out of the classroom without permission.
五、过去完成进行时
1.构成和意义:had been+v.-ing形式,表示过去某一时间之前一直进行的动作。
2.用法
(1)过去完成进行时表示动作在过去某一时间之前开始,一直延续到这一过去时间。和过去完成时一样,过去完成进行时也必须以某一过去时间为前提。
►I had been looking for it for days before I found it.这东西我找了好多天才找着。
(2)表示反复进行的动作。
►He had been mentioning your name to me.
他过去多次向我提到过你的名字。
[即时训练5]——单句语法填空
(1)They had been expecting (expect) the anecdote for some time before I came.
(2)The doctor asked what he had been eating (eat).
(3)She came back at seven.He had been waiting (wait) for her for 2 hours.
(4)We didn't go shopping yesterday because it had been raining (rain) all day.
(5)When Alice came to herself, she did not know how long she had been lying (lie) there.
六、过去完成时和过去完成进行时的区别
1.过去完成时
表示动作在过去的某一时间已经完成。
►Tom was disappointed that most of the guests had left when he arrived at the party.
当汤姆到达晚会的时候,大部分人都走了,他很失望。
2.过去完成进行时
表示在过去某一特定时间以前发生的动作一直持续到这个特定时间,或是刚刚结束,或是还要延续。但是,决不会延续到现在。
►It had been raining hard for three weeks.Nearly all the little trees on the mountain were washed away.大雨一连下了三个星期,山上的小树几乎都给冲走了。
[即时训练6]——补全句子
(1)她上大学以前一直在学英语。
She had been studying English before entering the college.
(2)她已经打扫过了,所以办公室很整洁。
She had cleaned the office , so it was very tidy.
(3)大雨已连续下了大约两天,这有可能造成洪灾。
The heavy rain has been pouring for about two days and it may lead to a big flood.
(4)我听说你一直在找我。
I heard you'd been looking for me .
维度一:基础题型训练
Ⅰ.单句语法填空
1.Its success is very encouraging in today's television world where reality shows have played (play) a leading part so far.
2.Tom was shocked to realise that the two-month summer vacation had passed (pass) before he knew it.
3.Facial recognition technology has been extended (extend) into many areas of school life so far.
4.This is the first time she has experienced (experience) disappointment.
5.By the end of last term, more than 3,000 English words had been learnt (learn) by us.
6.It was really annoying;I couldn't get access to the data bank you had recommended (recommend).
7.I had been studying (study) at home before my mother came back.
8.He has been coughing (cough) a lot recently.He ought to give up smoking and go to see a doctor.
9.He has been listening (listen) to English programs since he came to the US, so he has made (make) great progress.
10.A rescue worker risked his life saving two tourists who had been trapped (trap) in the mountains for two days.
11.I was sent to the village last month to see how the development plan had been carried (carry) out in the past two years.
12.China's high-speed railways have grown (grow) from 9,000 to 25,000 kilometers in the past few years.
维度二:语法与写作
Ⅱ.补全句子
1.为你做了很多,然而你进步却很小。
Enough has been done for you , but you've made little progress.
2.她刚要睡着,这时忽然被敲门声吵醒了。
Hardly had she fallen asleep when a knock at the door woke her up.
3.这是她第一次开车。
It is the first time that she has driven a car.
4.这是他本周第二次犯同样的错误。
It was the second time this week that he had made the same mistake .
5.我本打算帮你的,但当时我太忙了。
I had meant to help you, but I was too busy at that moment.
6.从今天早上到现在,我一直都在写信。
Since this morning I have been writing the letter .
维度三:语法与语篇
Ⅲ.根据汉语提示补全下面短文
I was reading today when I found it was snowing.Looking outside of the window, the shiny white snow on our lawn 1. had been cleaned by my father (已经被父亲打扫了).I closed the book that I 2. had borrowed from the local library (从当地图书馆借的) and went downstairs for breakfast, which 3. had been prepared well (已经准备好了) on the kitchen table.Then my little brother came to tell me that he 4. had finished all his homework (已经完成了所有的作业) and he had a very nice dream the night before.We 5. talked about his dream (谈论了他的梦) and the stories of my book.During the breakfast, one of my best friends came to visit my family.She said that she would go to Australia for further study.I know she 6. has been longing for the opportunity (一直期待这个机会) for a long time.During her study, she will learn the culture and professional knowledge in her field.I was so proud of her that we talked all day long.
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