现在完成时和过去式比较.ppt

1、a,1,现在完成时与一般过去时的比较 the present perfect tense & the simple past tense,a,2,一、现在完成时,1.结构：主语+（助动词）have/has+过去分词 表示过去发生或已经完成的某一动作对现在造成的影响或结果。 2. 可以和一些表示不确定的时间状语连用，如just, already, yet, ever, recently, so far等。例如： Weve done a lot of work on it, but we havent finished yet. 3. 表示动作或状态从过去某一时刻开始一直持续到现在，还可能持续下去

2、，常与for和since等引起的表示一段时间的状语连用。 Ive lost 7 kg in the last two months.,a,3,4. 表示说话前发生过一次或多次的动作，现在成为一 种经历，常带有twice, ever, never, three times, before等时间状语。例如： Ive never seen her as angry as that, so I kept quiet. Tips a. come, arrive, buy, hear等终止性动词的现在完成时一般不能与表示一段时间的状语连用。 He has joined the army for three

3、 years. (false) He has been a soldier for three years. (right) He has been in the army for three years. (right) b. hear等词的否定式可以与for等引起的表示一段时间状语连用。例如： I havent heard from you for weeks.,a,4,translation,我已经写完作业了。（finish） I have finished my homework already. 2. 他已经在这里工作五年了。（work） He has worked here for

4、 five years.,a,5,二. 一般过去时,1.结构：主语+动词过去式 2.表示过去某时发生的动作或存在的状态，常和a moment ago, half an hour ago, just now, yesterday, last week, in 2005, in those days, at that time等表示过去的时间状语连用。例： We soon became good friends. Two years ago, she bought an expensive bike. 3.表示过去时间内连续发生的几个动作。例如： At four oclock, Polly lef

5、t work and stepped out into the fog 4. 表示过去时间内经常或习惯性的动作或状态。例如: After lunch, we usually played on the school field.,a,6,Nothing is impossible.（写出下列动词的过去式） work rain watch wash 2.trip drop stop plan shop 3. cry copy try study 4. stay enjoy play destroy 5. live smile move like 6. come write fly buy,一般过

6、去时,came wrote flew bought,1. 动词 + ed,2. 末尾只有一个辅音字母的重读闭音节词,双写这个字母, 再+ed.,3. 辅音字母+y结尾的，变y为i，再+ed.,4. 元音字母+y结尾的，直接+ed.,5. 以e字母结尾的动词加d。,不规则变化需强记,a,7,我昨天去看电影了。 I went to a movie yesterday. 2. 我去年住在纽约。 I lived in New York last year. 3. 我刚才没有吃苹果。 I didnt eat an apple just now. 4. 我上个月买了一部新手机。 I bought a ne

7、w mobile phone last month. 5. 我前天参观了博物院。 I visited the museum the day before yesterday.,翻译,a,8,概念: 一般过去时表示在过去某个时间发生的动词或存在的状态，也表示过去经常或反复发生的动作。 e.g. He came here yesterday. 现在完成时表示过去的动作（或状态）对现在产生的影响和结果 e.g. He has broken his bottle.,一般过去时和现在完成时的区别：,a,9,1）构成不同 Tom went to London last year. Lily has bee

8、n to London twice. 一般过去时的谓语动词用过去式， 现在完成时的谓语用“助动词have /has +过去分词”,一般过去时和现在完成时的区别：,a,10,一般过去时和现在完成时的区别：,现在完成时是表示过去的动作与现在的联系，主要说明的是现在的情况和状态；而一般过去时则强调动作发生在过去某一时间，与现在不发生联系. e.g. We havent seen him since last year. 我们自从去年以来一直未见到他。（现在还未见到） We didnt see him last year. 我们去年没见到他。（现在不一定未见到） Who has opened the

9、door? 谁把门开了？（现在门还开着） Who opened the door? 谁开的门？ (指过去，与现在无关。现在门是关着还是开着，没有说明。) Have you had your lunch? 你吃过午饭没有？ （意即你现在不饿吗？） Yes, I have. 吃了。 （意即我现在饱了，不要再吃了。） When did you have it? 你什么时候吃的？ （说话人感兴趣的是“吃”这一动作发生在时。）,2）用法不同 I had supper an hour ago我一小时前吃的晚饭。（表示过去的动作） I have just had supper我刚刚吃过晚饭。（强调对现在的影

10、响我不饿） He was a teacher then他那时是个教师。（表示过去的状态） He has been a teacher since then他从那时起一直当教师。（她现在还是教师）,a,11,一般过去时的时间状语： yesterday, once, last week, . ago, in 1980, in October, just now等具体的时间状语。 现在完成时的时间状语： for, since, so far, ever, never, just, yet, till, up to now, always等不确定的时间状语。,一般过去时和现在完成时的区别：,3）所用时

11、间状语不同 The children went to the zoo last Sunday 上星期天，孩子们去了动物园。 I havent read the book before 我以前没看过这本书。 They lived here in 1980 他们一九八年住在这里。,一般过去时常与具体的时间状语连用，现在完 成时常与模糊的时间状语连用，或无时间状语。,a,12,Last Sunday,a,13,Correct the passage:,Last Sunday, Ted and his father are at home. They movd to a new house. His

12、father wantted to put the books in some boxes, but he cant find any boxes. Ted telled him the boxes was in the next room. Then he bought these boxes to his father.,moved,wanted,couldnt,told,were,brought,were,a,14,Exercises for the present perfect tense:,7. Is Tom doing his homework? No, he _his home

13、work already.(finish) 8. Do you know Miss King? No, but I _ her before .(hear of) 9. What about the film? Sorry, I dont know. I _ it yet. (see) 10. _ you ever _ to the Great Wall? No, never. ( go) 11. How does he get on with his classmate? Oh, he _ a lot these days. (change) 12. Help yourself , plea

14、se. No, thanks. Im full. I _ just _ three eggs.(eat),already,has finished,before,have heard of,yet,havent seen,ever,never,Have,been,these days,has changed,just,have,eaten,a,15,练习,1. -I have seen the film Titanic already. -When _ you _ it? A. have, seen B. will see C. did, see D. did, seen 2. Mr. Bla

15、ck _ in China since five years ago. A. lived B. has lived C. lives D. is going to live,3. - - _ Uncle Wang _ (mend) the TV yet? -Yes, he_. -When _ he _ it? - Yesterday. 4. -I _ (see) the film Chicken Run. - Where and when _ you _ (see) it? - Last week. 5. -_ you _ (see) the film last night? -No, I _

16、 (see) it for several times. 6. -_ you _ (return) the book to the library? - Not yet. But I _ (return) it this afternoon.,a,16,7. Is Tom doing his homework? No, he _his homework already.(finish) 8. Do you know Miss King? No, but I _ her before .(hear of) 9. What about the film? Sorry, I dont know. I

17、 _ it yet. (see) 10. _ you ever _ to the Great Wall? No, never. ( go) 11. How does he get on with his classmate? Oh, he _ a lot these days. (change) 12. Help yourself , please. No, thanks. Im full. I _ just _ three eggs.(eat),练习,a,17,Further exercises:,1. I am busy these day. I _ (not go) to the cin

18、ema for weeks. 2. The boy is happy because he _ (sell) out all the newspapers. 3. They _ (live) in Shanghai since 1991. 4. Great changes _ (take place) in our country since 1949. 5. Miss Jane _ (teach) us last year. She _(teach) in our school for 4 years.,6. She _ already _(do) her homework. She _(do) it yesterday evening. 7. -_ you ever _ to London? -Yes, I have. -When _ you _ (go) there? -Last year. 8. Who _ (take) my dictionary away? I cant find i