初中英语时态讲解及练习

初中英语动词时态的用法及练习姓名：____________ 一、一般现在时动词+s的变化规则1．一般情况下，直接加-s，如：cook-- cooks, milk-- milks2．以s. x. sh. ch. o结尾，加-es，如: wash-- washes, watch-- watches, go-- goes3．以“辅音字母+y”结尾，变y为i, 再加-es，如：study—studies一般现在时用法专练:一、写出下列动词的第三人称单数drink__________ go____________ stay____________ make__________ look___________ have____________ pass__________ carry __________ come__________ watch___________ plant____________ fly __________ study___________ brush____________二、用括号内动词的适当形式填空。

1.He often ______(have) dinner at home.2.We ___________(not watch) TV on Monday.3.The girl _______(teach) us English on Sundays.4. Mike _______(like) cooking.5. My aunt _______(look) after her baby carefully.6.I ____(be) ill. I’m staying in bed.7. She __________(go) to school from Monday to Friday.三、按照要求改写句子1. Daniel watches TV every evening.(改为否定句)_______________________________________________________2. I do my homework every day.(改为一般疑问句，作否定回答)___________________________________________五、单项选择题。

初中必备英语动词的时态技巧全解及练习题(含答案)一、初中英语动词的时态1．It’s nice to see you again. We ______ each other for a long time.A．didn’t see B．haven’t seen C．won’t see D．didn’t see【答案】B【解析】【详解】句意：再次见到你很开心，我们已经好长时间没见了。

本题考查的是时态，结合语境，此处指到现在为止有好久没有见面了，根据所给空后面的for a long time是现在完成时的标志词可知，应该用现在完成时，故答案选B。

2．—Shall we play tennis now?—Sorry, I can’t. I my homework.A．do B．did C．have done D．am doing【答案】D【解析】句意：——我们现在打网球去好吗？——对不起，我不能去，我在做作业。

A. do 做，用于一般现在时态，主语复数时； B. did做，用于一般过去时态； C. have done 做，用于一般现在完成时态； D. am doing做，用于现在进行时态，主语是I时；根据now可知用现在进行时态，故选D3．— Did you sleep well last night?—Far from that! One of my neighbours ▲ music pretty loud.A．plays B．was playing C．is playing D．would play【答案】B【解析】句意：-----你昨晚睡得好吗？------远非如此！我的一个邻居在大声演奏音乐。

A. plays一般现在时态；B. was playing 过去进行时态；C. is playing 现在进行时态； D. would play过去将来时态。

结合语境可知，昨晚睡不好觉的原因是当时有人在演奏音乐，故用过去进行时态来描述，答案为B。

初中英语8种时态复习I.时态详解一、一般现在时：概念：①表现在存在的状态；②现在经常、反复发生的动作。

时间状语：always,usually,often,sometimes,everyweek(day,year,month…),onceaweek,onSund ays,etc.基本结构：①主语+be（am,is,are）;②主语+行为动词原型（单三形式主语+动词单三形式）否定形式：①am/is/are+not;(is+not=isn’t;are+not=aren’t)②此时态的谓语动词若为行为动词，则在其前加don't,如主语为第三人称单数，则用doesn't，同时还原行为动词。

一般疑问句：①把be动词放于句首;②用助动词do提问，如主语为第三人称单数，则用does，同时，还原行为动词。

二、一般过去时：概念：①过去某个时间里发生的动作或状态;②过去习惯性、经常性的动作、行为。

时间状语：ago,yesterday,thedaybeforeyesterday,lastweek(year,night,month…),in1989,jus tnow,attheageof5,oneday,longlongago,onceuponatime,etc.基本结构：①主语+be（was,were）;②主语+动词过去式否定形式：①was/were+not;(was+not=wasn’t;were+not=weren’t)②在行为动词前加didn't，同时还原行为动词。

一般疑问句：①was或were放于句首;②用助动词did提问，同时还原行为动词。

三、现在进行时：概念：表示现阶段或说话时正在进行的动作及行为。

时间状语：now,look,listen,atthistime,thesedays,etc.基本结构：be(am,is,are)+doing否定形式：be(am,is,are)+not+doing.一般疑问句：把be动词放于句首。

初中英语语法一般现在时专项讲解及总结练习初中英语时态专题解说一般此刻时一、出现以下状况是用一般此刻时：常常性、习惯性的动作或存在的状态。

时间标记词：often常常，usually往常，always老是，every每个，sometimes有时，at在几点钟e.g.Igotoschoolonfoot.Heisverybusynow.Ioftendomyhomeworkat7:00.HeusuallygoestotheparkonSundaymorning.表示主语的特点、性格、能力、喜好等。

e.g.Hecanswim. Iworkhard. IlikewatchingTV.表示客观真谛e.g.Therearesevendaysinaweek.Themoonmovesroundtheearth.二、一般此刻时的句式变化：1)表示动作，一般人称作主语的，变否认句须在动词前加助动词don’t；变一般疑问句须在句首加助动词do。

E.g.一定句Theyhavelunchat12:00.否认句Theydon’thavelunchat12:00.疑问句Dotheyhavelunchat12:00? 一定回答：Yes,theydo.否认回答：No,theydon’t.2）单三人称做主语的，变否认句须在动词前加助动词doesn’t；变一般疑问句须在句首加助动词does。

e.g.一定句：Hegoestoschoolbybike. 否认句：Hedoesn’tgotoschoolbybike.疑问句：Doeshegotoschoolbybike? 一定回答：Yes,hedoes.否认回答：No,hedoesn’t1.She______(go)toschoolatseveno ’clock.否认句：一般疑问句：2.Theyusually_____upat17:00.(get)否认句：一般疑问句：3.Amy____(be)herejustnow.否认句：一般疑问句：实质演练1.Ihavemanybooks. （改为否认句）doeshishomeworkathome.否认句:一般疑问句：usuallywaterstheflowers.1初中英语时态专题解说否认句:一般疑问句YangusuallywashessomeclothesonSaturday. 否认句:5.IusuallyplayfootballonFridayafternoon. 否认句:一般疑问句：加强训练一、写出以下单词的第三人称单数形式1.work______ ____read__________clean__________write__________2.teach_____ _____wash__________guess__________watch__________3.go________ __do_________ __4.study_____ _____fly__________cry__________play__________5.have__________二．选择)1._____youhaveaboo k?A.DoB.AreC.Is D.Have)2.They_________onafarm .workingB.isworkC.working D.isworked)3.DoesPeterliketowatchTV?__________.A.Yes,helike B.No,hedoesn’tC.Yes,he’dlike D.No,helikes)4.Shedo esn’t__________herhomeworkintheafter noon.A.doingB.todoC.doesD.d o)5.How____________Mr.Brown___________toAmerica?A.do,goB.is,goC.does,go )6.Where’smy camera?I____________it.A.amnotfinding B.amnotseeing C.can’tfindD.can’tl ookat)7.How___________hegotowork?He___________toworkbybike.A.does;g oB.do;goesC.do;go D.does;goes)8.______youusuallylateforschool?No,_____ ________.A.Do;IamB.Does;notC.Are;I’mnotD.Are;Iaren’t)9._____she_____homeatsixeveryday?A.Is,leave B.Does,leave C.Is,leavesD.Does,le ft)10.Mr.Yang____________Englishthisterm .A.teachesour B.teachesus C.teachsusD.teachou r三．用所给动词的适合形式填空。

初中英语八大时态用法详解及真题巩固练习一般现在时1. 概念：经常、反复发生的动作或行为及现在的某种状况。

2. 基本结构：①is/am/are；②do/does否定形式：①am/is/are + not ; ②此时态的谓语动词若为行为动词，则在其前加don't,如主语为第三人称单数，则用doesn't，同时还原行为动词。

3. 一般疑问句：①把 is/am/are 动词放于句首；②用助动词do提问，如主语为第三人称单数，则用does，同时，还原行为动词。

4. 用法：1) 经常性或习惯性的动作，常与表示频度的时间状语连用。

例如：I leave home for school at 7 every morning. 每天早上我七点离开家。

2) 客观真理，客观存在，科学事实。

例如：The earth moves around the sun. 地球绕太阳转动。

Shanghai lies in the east of China. 上海位于中国东部。

3) 表示格言或警句。

例如：Pride goes before a fall. 骄者必败。

注意：此用法如果出现在宾语从句中，即使主句是过去时，从句谓语也要用一般现在时。

例如：I knew that the earth goes around the sun when I was little.我小时候就知道地球绕太阳转。

4) 现在时刻的状态、能力、性格、个性。

例如：I don't want so much. 我不要那么多。

Ann writes good English but does not speak well.安英语写得不错，讲的可不行。

5) 一般现在时表示将来含义a. 下列动词 come, go, arrive, leave, start, begin, return 的一般现在时可以表示将来，主要用来表示在时间上已确定或安排好的事情。

一般现在时知识精讲一、一般现在时表示通常性、规律性、习惯性、真理性的状态或者动作有时间规律发生的事件的一种时间状态。

二、句子结构主语（第一/二人称/第三人称复数）+do (动词原形)主语（第三人称单数）+does (动词三单形式)主语+am/ is /are三、基本用法四、时间状语1. 表示频率的副词: always, usually, often, sometimes, never, hardly, seldom…2. every/once+名词: every day/ week/ year, once a week/ month …3. 表示时间的短语: twice a day, on weekends, on Mondays…五、一般现在时动词三单的变化规律六、相关句式三点剖析一、考点：时态是英语学习中的核心内容之一，是英语学习的基础。

自然，时态考查是各种英语考试尤其是中考时的座上宾。

动作发生的时间决定时态，时态决定动词的形式，而考卷中的时态题通常没有给出明确的时间标志词，考试需领悟所提供的语境来做出判断。

只有推断出动作发出的正确时间，才可能正确答题，这就要求考生在熟练掌握时态结构、用法并牢记常用的时间状语的基础上，要充分利用上下文中隐含的信息来捕捉时间，找准答题的突破口。

二、重难点：一般现在时在考试中的重难点是：句子结构、基本用法、标志时间状语、动词三单的变化规则及相关句式的变化。

三、补充点：1. 表示按计划或安排好的，或将要发生的动作，可用一般现在时表将来。

但只限于start, begin, leave, go, come, arrive, return, take place等。

例：My train leaves at 7:00 this afternoon.我乘坐的火车将在今天下午7点离开。

2. 在复合句中，当主句是一般将来时，时间或条件状语从句的谓语动词只能用一般现在时来表示将来要发生的动作。

初中英语语法专项复习：英语各个时态和语态讲解及练习题初中英语有16种时态,但是常用的只有9种：一般现在时、一般过去时、一般将来时、现在进行时、过去进行时、现在完成时、过去完成时、过去将来时、现在完成进行时;下面分别介绍;1、一般现在时的用法1 一般现在时表示经常性、习惯性的动作；表示现在的状态、特征和真理;句中常用always,usually,often,sometimes,seldom,rarely,never,every daymorning,Monday,week,...etc.,every there years,once a weekday,month,...etc.,...等时间状语;例如：a. He goes to school every day.b. He is very happy.earth moves around the sun.2 在时间状语从句和条件状语从句中,用一般现在时表示将来;例如：a. If you come this afternoon, we’ll have a meeting.b. When I graduate, I’ll go to countryside.2.一般过去时的用法1 表示过去某时间发生的事、存在的状态或过反复发生的动作;常和:last weeknight,Monday,month,year,...etc.four years agodays,month,...etc.before1980three,liberation,从句,...etc.the day before yesterday,the day before last,the year before last,just now,a monent ago,yesterday,yesterday morning,this morning,at first,at last,in the end,finally,then,..a. He saw Mr. Wang yesterday.b. He worked in a factory in 1986.2表示过去经常发生的动作, 也可用“used to “ 和“would + 动词原形”; I used to smoke. During the vacation I wouldm in the sea.注：”used to “ 表示过去常发生而现在不再发生的动作或存在的状态;a. I am used to the climate here.b. He is used tomming in winter.3.一般将来时的用法一般将来时表示将来的动作或状态;其表达形式除了“ will 或shall + 动词原形”表示即将发生的或最近打算进行的事;常和：next weekMonday,month,year,...etc.in three daysan hour,...etc.tomorrow,tomorrow morning,the day after tomorrow,the day after next,the year after next,tonight,in 20102016...etc.this evening,this Saturday,after Wednesday,soon,sometime next week,one day in futuer,sooner or later,...1be going to do 结构It is going to rain.We are going to have a meeting today.2 “be about to + 动词原形” 表示即将发生的动作,意为be ready to do sth. 后面一般不跟时间状语; We are about to leave.3 go , come , start, move, leave, arrive ,stay 等可用进行时态表示按计划即将发生的动作;I’m leaving for Beijing.4.现在进行时的用法1 现在进行时表示现在正在进行的动作,由“ be + 现在分词” 构成;常和：now,these daysweeks,months,...etc. this monthweek,...etc.Look,Listen,...另外, “系动词+ 介词或副词” 也表示进行时的意义;What are you doingThe bridge is under construction.2 表示感觉、愿望和状态的某些动词如have, be , here, se, like 等一般不用进行;5.过去进行时的用法1 过去进行时过去某一时刻、某一阶段正进行的动作,由“ was were + 现在分词”构成;常和：this time yesterday,this time last Friday,in those days,at nine last night,from one to three yesterday afternoon,...In 1980 he was studying in a university.He was reading a novel when I came in.6.现在完成时的用法现在完成时由“have/has + 过去分词.其使用有两种情况：1 现在完成时所表示的动作在说话之前已完成,但对现在有影响;句中没有具体时间状语;常和：just,alreadly,yet,never,ever,now,before,this week,today,these days,once,twice,three times,...He has gone to Fuzhou.He has been to Fuzhou.2 现在完成时所表示的动作开始于过去,持续到现在,也许还会持续下去常用for 和since表示一段时间的状语或since then1949,last Monday,two o'clock,从句...,etc.,ever since then,for three daysa long time,two hours,...etc.so far , now, today, this wek month, year 等表示包括现在内的状语;He has studied English for 5 years.He has studied English since 1985.Now I have finished the work..注意：表示短暂时间动作的词如come, go , die, marry, buy 等的完成时不能与for, since 等表示一般时间的词连用;正确：I have bought the book already.错误：I have bought the book for two years.改：I have had the bookl for two years.7．过去完成时的用法1 过去完成时由“had + 过去分词”构成;过去完成时的动作表示过去某一时刻或某一时刻或某一动作之前完成的动作或状态;句中常用by then1977,yesterday,eight last night,the time we got there,...etc.by the end of last termweek,year,month,...etc..by, before, until, when 等词引导的时间状语;By the end of last year we had built five new houses.I had learnt 5000 words before I entered the university.2过去完成时的动词还可表示过去某一时刻之前发生的动作或状态持续到过去某个时间或持续下去;Before he slept, he had worked for 12 hours.8．过去将来时的用法过去将来时表示从过去的某个时间看来将要发生的动作或存在的状态;过去将来时由“should 或would + 动词原形” 构成;第一人称用should, 其他人称用would. ;常和：They were sure that they would succeed.二动词语态1．当句子的主语是动作的执行者时, 谓语的形式叫主动语态;句子的主语是动作承受者时,谓语的形式叫被动作语态;被动语态由助动词be + 过去分词构成,时态通过be 表现出来;1 一般现在时：You are required to do this.2 一般过去时：The story was told by her.3 一般将来时：The problem will be discussed tomorrow.4 现在进行时：The road is being widened.5 过去进行时：The new tool was being made.6 现在完成时：The novel has been read.7 过去完成时：He said that the work had been finished.8 过去将来时：He said that the trees would be planted soon.2. 一些特殊的被动结构1 带情态动词的被动结构：The problem must be solved soon.2 带不定式的被动结构：The room is going to be painted.The homework needs to be done with care.3 短语动词的被动：a.不及物动词+介词：若这类短语动词是及物性的,则可用于被动语态中,如：laugh at, look after, talk about, think of 等;若这类短语动词是不及物性的则不可用于被动语态中,如：book up, look down. 等b.及物动词+副词：bring about, carry out, find out, make out, put away, put off, take up, turn down, turn out, wipe out 等c. 动词+副词+介词：do away with, face up to, give into ,look down upon, make up with等d. 动词+名词+介词：catch sight of, keep on eye on, make a fool of , pay attention to , put an end to , set fire/light to , take notice of 等4 带复合宾语的动词在改为被动语态时,一般把主动结构中的宾语改为主语,宾语补足语保留在谓语后面;We always keep the classroom clean.比较：The classroom is always kept clean.5主动形式表示被动意义的词;常见的有：a.主动形式,这时动名词同句中的主语有动宾关系;The children need looking after.The windows wants /requires repairing.This point deserves mentioning.练习题1. It is a fine day. The sun __________shine brightly.2. They ___________visit the Science Museum next Sunday.3. Mr Brown________live in Beijing since he came to China.4. Mr Wang ________teach us English two years ago.5. The Smiths _______________ watch TV at this time last night.6. We __________learn about ten English songs by the end of last term.7. Father said that he ____________buy a new bike for me the next Friday.8. Bill isn¡¯t here. He ___________chat with his friends in the classroom.9. The teacher said that the moon __________go round the earth.10. The Young Pioneers will go to the zoo if it ____________not rain this Sunday.11. Listen They __________talk about the new film.12. Jim asked us what ___________happen in China in 1976.13. My mobile phone ___________steal on a bus last week.14. The host ____________interview the little boy just now.15. The Greens __________watch TV now.16. He said that he _____________ring me up when he got there.17. We ____________learn English for about three years.18. My brother_____________join the League in 1997.19. The farmers __________pick apples when I saw them.20. The red skirt __________cost the girl forty yuan.21. The film ____________begin when I got to the cinema.22. The girl told me that she wanted to be an English teacher when she _____grow up.23. My sister is a student and she _____________study at a middle school nearby.24. Mr Green __________travel to several places in South China since he came here.25. You _________catch the early bus if you get up early.26. _______you been________wear glasses all the time27. I’ll go home as soon as I _______finish my homework.29. Most science books are ______write in English.30. I ____________stay there for two months last year.31. Tell Lily to call me as soon as she _______.A. will arriveB. gets thereC. has goneD. reach here32. ----Hi, Kate. You look tired. What’s the matter ----I ______ well last night.A. didn’t sleepB. don’t sleepC. haven’t sleptD. won’t sleep33. ----Excuse me, look at the sign over there, please. Could you stop smoking----Sorry, I ____ that.A. didn’t seeB. don’t seeC. won’t seeD. can’t see34. ----Well, I found this. I think it must be yours. ----My watch Thank you. Where _____itA. do you findB. had you foundC. were you findingD. did you find35. ----Don you know when Dr White ____ for dinner this evening----No, but I think he ____ when he is free.A. will come; comesB. will come; will comeC. comes; comesD. comes; will come36. Look at those black clouds. It _____ rain. Let’s hurry. A. maybe B. would C. has D. is going to37. ----Jimmy is leaving for a holiday. ----Really Where ____ he ____A. has; goneB. will; goC. did; goD. does; go38. ----Shall we go shopping now ---Sorry, I can't. I ____ my shirts.A. washB. washesC. washedD. am washing39. ----I called you yesterday evening, but there was no answer.----Oh, I am sorry. I ___ dinner at my friend's home.A. haveB. hadC. was havingD. have had40. The Oriental Pearl TV Tower ____ thousands of visitors since 1995.A. attractedB. attractsC. has attractedD. will attract46. ----Why didn't you go to the cinema yesterday -----Because I ____ the film before.A. had seenB. have seenC. have watchedD. has watched47. I don't think John saw me. He ____ a book at that moment.A. just readB. has just readC. was just readingD. had just read48. Mr Smith ____ a book about China last year but I don't know whether he has finished it.A. has writtenB. wroteC. had writtenD. was writing49. Mr White ____ the newspaper while his daughter ____TV.A. has read; was watchingB. was reading; watchedC. was reading; was watchingD. reading; watched50. ---- I ____ you at the meeting. Why ----I was ill. A. saw B. have seen C. not see D. didn't see51. The 29th Olympic Games ____ in Beijing in 2008. A. hold B. will hold C. will be held D. held52. Hurry up The play ____ for ten minutes. A. has been on B. has begun C. had begun D. began53. ----May I speak to Mr Smith ----Sorry, he ____ Australia. But he ____ in two days.A. has been to; will come backB. has gone to; will be backC. has been in; would come backD. is leaving for; doesn't come back54. I can't go to the theater tonight because I ____ my ticket.A. have lostB. had lostC. will loseD. was losing55. ----What a nice bike How long ____ you ____ it ----Just two weeks.A. have; boughtB. did; buyC. have; hadD. are; having56. ----I'm sorry to have kept you waiting. ----Oh, not at all. I ____ here only for a few minutes.A. have comeB. had beenC. wasD. have been57. ----____ my dictionary anywhere ---- Yes. I saw it on your desk a moment ago.A. Did you seeB. If you seeC. Had you seenD. Would you see58. We were all surprised when he mad it clear that he ____ office soon.A. leavesB. would leaveC. will leaveD. had left答案：I. 1. shines/ is shining 2. are going to/ will visit 3. has lived 4. taught5. were watching6. had learned7. would buy8. is chatting9. goes 10.doesn't rain 11. are talking 12. happened 13. was stolen 14. interviewed15. are watching16. would ring 17. have learned 18. joined 19. were picking 20. cost21. had begun 22. grew 23. studies 24. has traveled 25. will catch26. Have; wearing 27. finish 28. haven't heard 29. written 30. stayedII. 31--35 BAADB 36--40 DBDCC 41--45 ACBAC 46--50 ACDCD51--55 CABAC 56--60 DABDA 61--65 BDBAB 66-70 BDABC 71--75 BCADD。

初中英语语法:八种时态详解与练习一．概念：英语中表示不同时间发生的动作或存在的状态，需用不同的动词形式表示，这种不同的动词形式称为时态。

二．种类：（基本时态）一般现在时一般过去时现在进行时过去进行时一般将来时过去将来时现在完成时过去完成时一般现在时一、概念：经常、反复发生的动作或行为及现在的某种状况。

二、常搭配的时间状语：always, usually, often, sometimes, every week (day, year, month…), once a week,on Sundays, etc.三、基本结构①be动词（is,am,are）；②行为动词(主语是第三人称单数时谓语动词要加s或es外) 否定形式：①am/is/are+not;②此时态的谓语动词若为行为动词，则在其前加don't,如主语为第三人称单数，则用doesn't，同时还原行为动词。

一般疑问句：①把be动词放于句首；②用助动词do提问，如主语为第三人称单数，则用does，同时，还原行为动词。

例句：I go to school at 6 every morning. 每天早上我七点去上学。

Summer follows spring. 春天之后是夏天。

I learned that the earth goes around the sun when I was in primary school. 我在小学就学过地球是围绕太阳转的。

Pride goes before a fall. 骄者必败。

四、基本用法：1) 描述当前时间内经常出现、反复发生的动作或存在的状态。

在这种情景中，句子常带有表示频率的时间状语：always , everyday , often , once a week (month , year , etc.) , sometimes , seldom , usually等等，以表示句中的动作或状态是习惯性的、经常性的。

初中重点语法：一般现在时第一部分：定义与详解第二部分：练习和语法解析一、定义与讲解一般现在时：表示经常性，习惯性的动作或状态。

时间状语：often 经常，usually通常，always 总是，every每个，sometimes 有时，never从不，seldom 极少结构：动词原形（第三人称单数+s/es）。

第三人称单数变化：(1)直接在动词词尾加-s.ask---asks work---works get---gets stay---stays(2)以字母s, x, ch, sh或o结尾的动词，在词尾直接加-es.watch---watches wish---wishesfix---fixes do---does go---goes pass---passes(3)以“辅音字母加- y”结尾的动词，要先变y为i再加-es.try---tries study---studies cry---cries fly---flies2.不规则变化：be---- is are have----has二、一般现在时用法图片1. 表示经常性，习惯性,永久性的动作或存在的状态。

通常与副词sometimes, often, usually, always, every day (year, month ), once (twice, three times) a day,等时间状语连用。

例：They usually go to school by bike.I take the medicine three times a day.She helps her mother once a week.Mary’s father is a policeman.There are 50 students in my class.2. 表示客观真理，科学原理，自然现象，等客观事实或格言，谚语等。

例：The sun rises in the east and sets in the west every day.Tomorrow is Tuesday.三、一般现在时的句型转换(1)当句子中有be动词或情态动词时，则把be动词或情态动词(can,could等等)提到主语的前面变成疑问句;在be动词或情态动词后面加not变成否定句.例：①陈述句：She is a student.疑问句→Is she a student?否定句→She is not a student.②陈述句：I can swim.疑问句→Can you swim？否定句→I can not swim.(2) 当句子中即没有be动词，也没有情态动词时，则在主语前加助动词do (you,以及复数), does(单数she,he,it)变成问句;在主语后谓语动词前加助动词don’t(I,you,以及复数), doesn’t(单数she,he,it)变成否定句，助动词后的动词要变成动词原形。