八年级英语现在完成时.doc

5现在完成时讲解与练习 一、意义和构成：现在完成时用来表示之前已发生或完成的动作或状态，但它的影响现在还存在；也可表示持续到现在的动作或状态。其构成： have (has) +过去分词。规则变化的过去分词与过去式的变化一样，在动词词尾加ed; 不规则变化的过去分词见不规则动词表。句式结构：1）. 肯定陈述句： 主语have (has) +过去分词其它 He has already finished his homework.2）否定陈述句：主语have( has)（not）+过去分词其它。He hasnt finished his homework yet. have not=havent has not=hasnt.3） 一般疑问句：Have( Has )主语过去分词其它？Has he finished his homework yet?-Yes, he has./ No, he hasnt./ No, not yet4） 特殊疑问句：特殊疑问词have(has) +主语+ 过去分词其它？How long have you 二、用法一：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。常与just（刚刚），already（已经），never（从来没有），ever（曾经），before（以前），yet（仍然），once（一次），twice（两次），many times（很多次），how many times（多少次），so far（迄今为止），during the past（last）three years（最近三年来）等连用。 副词的位置：just常用于肯定句中，放在have / has后，He has just come . never表示否定, 放在have / has后, He has never visited the Great Wall. ever用于疑问句中,句型为: Have / Has主语ever 过去分词？“曾经过吗？”用于询问某人过去的经历。Have you ever been to the farm？ before用于句末，The woman has never heard of that before. yet 用于句末或not 之后.Has the train arrived yet? No, not yet. already用于肯定句, have / has 之后或句末.We have already finished it. so far用于句首或句末. So far, we have visited the moon. 用法二：表示过去已经开始，一直延续到现在的动作或状态。时间状语有： for表示一段时间的词语I have taught English for 19 years。 since表示过去时间点的词语He has been at this school since 1986. since表示过去的时间状语从句I have lived here since I was born. since一段时间ago. I have known him since 20 years ago. 三、现在完成时态中可以和表示一段时间状语（for，since，how long, all ones life）连用的动词必须是表示延续的情况或动作的动词，即延续性动词。如：be，have，know，live，work，study，learn，teach，keep，speak，talk，draw，wait，wear，walk，sleep，drive，write，do，clean等。 I have been a teacher for nearly 20 years. How long has he lived here? 四、延续性动词的现在完成时可和包括“现在”在内的（到说话时仍未结束）表示一段时间的状语连用。如this morning，today，this week，these days He has been to Beijing three times this year. He has written two letters this morning.（说话时间在上午）He wrote two letters this morning.（说话时间在下午或晚上）五、用相应的延续性动词替代非延续性动词。 常见的相应转换形式如下: borrow / lendkeep, buyhave, finish / endbe over, arrive /come / go / move / reach /get tobe in /at / be here /be there, begin / startbe on , openbe open , closebe closed, diebe dead , leavebe away（from）, go to schoolbe in school / be a student, get upbe up, fall asleepbe asleep , fall illbe ill, get to knowknow, losebe lost, becomebe, return / come back / get backbe back, joinbe in / be amember, join the armybe in the army /be a soldier, receive / get a letterhave a letter , catch / get a coldhave a cold, begin to studystudy, 六、现在完成时中应注意的几个问题1. have been to 和have gone to的区别 have been to 强调“去过”，现已不在那里，如： He has been to the USA three times. 他到美国去过三次。（过去“到美国”，现在已“不在美国”） have gone to主要强调的是“去了”，现在人不在说话的现场，如： -Wheres your mother? -你妈妈在哪？ -She has gone to the hospital. -她去医院了。 2. have been to 和have been in的区别 have been to强调人“已回到原地”，后面可接表示“次数”的状语。 eg. She has been to Shanghai only once. -How many times has he been there? -Hes been there many times. have been in表示某人“已在某地停留一段时间，现仍在那里”，其后常带表示一段时间的状语。 eg. They have been at the bus stop for half an hour.他们在车站呆了半小时。（现在仍然在车站） We have been in Xian for two weeks. 我们在西安呆了两个多星期。（现仍在西安） How long have they been in China? 他们在中国呆了多长时间了？（仍在中国） 七、 一般过去时和现在完成时的动作都发生在过去,但意义却不同. （1）一般过去时只表示过去的动作或状态,和现在不发生关系。 现在完成时表示过去发生的某一动作对现在造成的影响,强调的是现在。 如:I learned ten English songs（说明过去学过,现在是否记得,不是本句的内容） I have learnt ten English songs.（learn发生在过去,但强调我现在懂英语歌曲） （2）一般过去时可以和表示过去的时间状语连用,如:yesterday, last year, three days ago, just now, 等。现在完成时不能和表示过去的时间状语连用,其时间状语可以是since,for , just, ever, never, before, already, yet , so far, all ones life等 八、规则动词的过去分词和它的过去式相同,即在原形后加ed（d）。已学近80个不规则动词的过去分词约有半数也和它的过去式相同,分类如下,利于记忆: 1) 原形中的元音字母有变化: get-got-got, sit sat-sat win-won-won spit- spat- spat shine shone- shone find- found- found hold-held-held meet- met-met stand- stood-stood understand-understood-understood feed- fed-fed hang-hung-hung 2) 原形中的辅音字母有变化:make-made-made spill-spilt-spilt have/ has-had-had build-built-built send-sent-sent lend- lent- lent spend-spent-spent 3) 在原形后加t或d: spoil-spoilt-spoilt learn-learnt-learnt mean-meant-meant hear-heard-heard pay-paid-paid say-said-said lose-lost-lost lay-laid-laid 4) 原形中的元音字母和辅音字母都有变化: feel-felt-felt smell-smelt-smelt spell-spelt spelt keep-kept-kept sleep-slept-slept sweep-swept-swept leave-left-left sell-sold-sold tell-told-told catch-caught-caught teach-taught-taught buy-bought-bought bring-brought-brought think-thought-thought wear-wore-worn 5) 与原形相同: hit-hit-hit hurt-hurt-hurt let-let-let put-put-put read-read-read set-set-set shut-shut shut cost-cost-cost cut-cut-cut 还有些不规则动词的过去分词与过去式不相同,为便于记忆,也分类如下: 1)原形中的元音字母有变化: ring-rang-rung sing-sang-sung drink-drank-drunk swim-swam-swum begin-began-begun sink-sank-sunk 2) 在原形上加en: eat-ate-eaten fall-fell-fallen ride-rode-ridden write-wrote- written be-was/were-been rise-rose-risen forget-forgot-forgotten 3)在原形上加n: see-saw-seen give-gave-given drive-drove-driven take-took-taken mistake-mistook-mistaken draw-drew-drawn blow-blew-blown grow-grew-grown know-knew-known show-showed-shown throw-threw-thrown 4)在过去式上加n: steal-stole-stolen break-brokenbroken choose-chose-chosen speak-spoke-spoken wake-woke-woken 6) 与原行相同:come-came-come run-ran-run become-became-become 7) 原形、过去式和过去分词都不相同的: do-did-done go-went-gone fly-flew-flown lie-lay-lain 个别动词有两个过去式和过去分词,一个为规则变化,另一个为不规则变化learn-learned-learned shined-shined smell smelled-smelled learnt-learnt shine shone-shone smelt-smelt wake -waked-waked spelled-spelled woke-woken spell -spelt spelt一、单项选择1. Oh, Mrs. King, your necklace looks nice. Is it new? No, I _ it for two years. A. had B. have had C. bought D. have bought 2. His grandfather _ for over two years. A. has died B. has been dead C. has dead D. died 3.Uncle Li can speak English very well because he _ England for 5 years. A. has gone to B. has been to C. has come to D. has been in 4. Where is Mr. Zhang? He _ London. A. has been to B. has been C. has gone D. has gone to 5. _ to the United States? No, never, but I went to Canada a few years ago. A. Have you been B. Have you gone C. Did you go D. Will you go 6. I havent seen you _ last Friday. A. for B. since C. from D. on 7. John, you _ the computer game for two hours. Its bad for your eyes. Stop, please! OK, Mum. A. played B. have played C. were playing D. play 8.I wont go to the concert because I _ my ticket. A. lost B. dont lose C. have lost D. will lost 二、用所给动词的适当形式天空1. It （rain）for a week. 2. I dont know this woman. I （meet, never）her. 3.Lets go to the cinema.No, I （see, already）the film. 4. We （finish, not）our homework yet. Will you wait a minute? 5. John （come, not）yet. He will be back in a minute. 6. Mr. Green often goes to America. In fact, he （be）there ten times. 7. Wheres John? He just （go）to the teachers office. 8. She （study）English since she was ten. She （begin）to study English when she was ten. 9. Jim isnt here. He （go）to the library. He （go）there an hour ago. 10. He （travel, never）on a train in her life. 11. I （buy）the bike two weeks ago. I （have）this bike since the beginning of this month. 12. Great changes （take place）in those villages in the last ten years, Great changes （take place, also）in my hometown in the last ten years. 13. How many times you （phone）me these days? you （phone）me this morning? 14. Tom cant get into the room because he （lost）the key to the door. 15. I （look）for the dictionary, but I （find not）it yet. 16. the new programmes （start）yet?No, they （plan,still） 18. We （live）in Shanghai from 1989 to 1999. We （live）for 10 years. 19. They cant go with us. They （finish, not）the work yet. 20. You （change, not ）your mind, havent you? 三、现在完成时态1have / has +done,请注意与一般过去式的区别 1 I have already worked out this math problem? (改为否定句) I worked out the math problem . 2 He has already finished the book.(改一般疑问句并做肯定否定回答) he the book ? Yes, he . No, he . 3 I have a book. (改一般疑问句并做肯定和否定回答) y