小学英语现在完成时讲解

现在完成时指的是过去发生并且已经完成的动作对现在造成影响或后果，过去某一时间开始并一直持续到现在并且有可能还会持续的动作或状态。一、基本结构：主语+have/has+动词的过去分词①肯定句：主语+have/has+动词的过去分词+宾语.②否定句：主语+have/has+not+动词的过去分词）+宾语.③一般疑问句：Have/Has+主语+动词的过去分词+宾语.④特殊疑问句：特殊疑问词或词组+一般疑问句（have/has+主语+过去分词（V-ed）+其他）过去分词变化规则如下：1、规则动词：规则动词的过去分词的构成规则与规则动词的过去式的构成规则相同。四点变化规则：1）一般动词，在词尾直接加“ed”。work---worked---worked,visit---visited---visited（2）以“e”结尾的动词，只在词尾加“d”。 live---lived---lived,（3）以“辅音字母+y”结尾的动词，将"y"变为"i"，再加“ed”。study---studied---studied,cry---cried---cried（4）重读闭音节结尾，末尾只有一个辅音字母，先双写该辅音字母，再加“ed”。stop---stopped---stopped,drop---dropped--dropped、不规则动词变化需参看不规则动词表逐一熟记。例如;cut-cut-cut,hit--hit--hit.二、用法1、现在完成时用来表示过去发生或已经完成的动作对现在造成影响或后果。也就是说,动作或状态发生在过去但它的影响现在还存在，强调的是现在。例如：Ihavealreadypostedthephoto.我已经把照片寄走了。强调post对现在的影响“照片不在这里”。2、现在完成时可以用来表示发生在过去某一时刻的,持续到现在的动作（用行为动词表示）或状态（be动词表示），常与for（+时间段）⑼nce（+时间点或过去时的句子）连用.谓语动词必须是延续性动词。例如：Hehaslivedheresince1978.自从1978年以来，他一直住在这儿。（动作起始于1978年，一直住到现在，可能还要继续住下去。）注意：for和since的用法。①for+时段为.…时间②since+过去一个时间点（译为：自从……以来）③since+时段+ago④since+从句（过去时）⑤Itis+时段+since+从句（过去时）注：瞬间动词（buy,die,join,lose）不能直接与for或since引导的时间段连用。要改变成延续性动词。变化如下：come/arrive/reach/getto beingoout beoutfinish beoveropen beopendie bedead Buy---have Fallill---beillComeback---bebackPuton---beon/wear Worry---beworriedCatchacold---haveacold三、现在完成时往往同表示不确定的过去时间状语连用，如already（肯定），yet（否定，疑问）,just,before,recently,still,lately,never等.例如:Hehasalreadyfinishedthework..典型例题1：Hisfatherthepartysince1978A.joindB.hasjoinedC.wasinD.hasbeenin解析：本题考查学生对现在完成时的熟练掌握。since1978表达“自从1978年一直到现在”，表示这件事情从过去一直持续到现在，应该用现在完成时，而且动词必须是延续性动词，AB均为瞬间动词，不能与时间段连用，故排除；C为一般过去时，也不行。答案；D.要牢记：一般过去时通常与表示过去的时间状语连用。如：yesterday,lastweek,twoyearsago,justnow,in2002等；而现在完成时则常与just,already,ever,never等副词和thesedays,thisweek,since ,for 等表示一段时间的状语连用。现在完成时强调过去发生的动作对现在的影响和结果，而一般过去时与现在没有联系，只是说明某个动作发生的时间是在过去。典型例题1：— you___yourhomeworkyet?—Yes.I itamomentago.A.Did;do;finishedB.Have;done;finishedC.Have;done;havefinished解析：本题考查一般过去时和现在完成时的用法区别。问句中的yet表明应该用现在完成时，而回答中的amomentago是一个表示过去的时间状语，应该用一般过去时。答案：B小学语法之一现在进行时一、现在进行时的定义，构成，标志性词语定义：表示现在或现阶段正在进行或发生的动作或存在的状态。构成：由be(am/is/are)+动词-ing形式构成标志性词语："now""look""listen""atthe(this)moment”.eg:Iamdoingmyhomeworknow.eg:Look!Mymotherisrunning!!!eg:Listen!Theyarereading.eg:Atthe(this)moment,heisonlyweeping.二、动词现在分词的构成规则1一般情况下直接加ingthink—thinkingsleep—sleeping study—studying speak—speakingsay—saying carry—carrying wake—waking2以不发音的字母e结尾的单词，去掉字母e,再加ingcome—coming make—making leave—leaving have—havingtake—taking3以重读闭音节(重读闭音节即两个辅音中间夹一个元音并且重读的音节)结尾，呈现“辅，元，辅”结构的动词，双写末尾的辅音字母，再加ingstop—stopping sit—sittingrun—running forget—forgettingbegin—beginning这类词还有：bigin,cut,get,hit,run,set,sit,spit,stop,swim,beg,drop,fit,nod,dig,forget,regret,rid,等。4以ie结尾的单词，现将ie变成y,再加inglie-lying;die-dying;三、现在进行时的用法(1)用来表示说话时正在进行或者发生的动作，例如：Motheriscookinginthekitchen.妈妈在厨房里煮饭。Whatareyoulookingat?你在看什么？(2)用来表示现阶段正在进行的动作(但说话时不一定在进行)，例如：Isshewritinganovel?她正在写一本小说吗？(3)用来表示即将发生的动作，一般是指按计划或者安排好要发生的动作。适用于这种情况的动词主要有：go,come,leave,start,arrive等。例如：I'mgoinghomeinhalfanhour.我一个半小时内要回家。Thetrainisarrivingsoon.火车很快就要到达了。四、现在进行时的句型变化肯定式结构：主语+be+动词-ing形式+其他.例如：Wearerunningnow.否定式结构：主语+be+not+动词-ing形式+其他.例如：Theyaren'tdoingtheirhomework.一般疑问句式结构：Be+主语+动词-ing形式+其他？例如：IsshehavingEnglishlesson?回答：肯定Yes,sheis.否定：No,sheisn't.特殊疑问句式结构：疑问词+be+主语+其他？例如：Whatishedoingnow?回答：Heisswimming.现在进行时专项练习：一、写出下列动词的现在分词：playrunswimmakegolikewriteskireadhavesingdanceputseebuyjoglivetakecomegetstopsitbeginshop二、用所给的动词的正确形式填空：I.Theboy(draw)apicturenow.Listen!Somegirls(sing)intheclassroom.Mymother(cook)somenicefoodnow.Whatyou(do)now?Look!They(have)anEnglishlesson.They(not,water)theflowersnow.Look!thegirls(dance)intheclassroom.Whatisourgranddaughterdoing?She(listen)tomusic.It's5o'clocknow.We(have)suppernowHelen(wash)clothes?Yes,sheis.NancyandIare(make)amodelplane.Look,heis(clean)thewindows.Theboys(run)withthecatnow.Ican't(skate),butIcan(ski).Thestudentsare(draw)intheclassroom.MysisterandIlike(listen)tomusic.Myfather(watch)TVinthebedroomnow.There(be)alampnearthesofa.Whathe(do)now?He(swim).Ilike(jog).Ican(jog).Iam(jog)inthestreetnow.Myparents(be)teachers.How(be)yourfather?He(be)fine.Iam(ride)abikenow.Look,Nancy(ride)abikewithme.Kate(dance).MikeandHelen(skate)now.SuHai(wash)clothesnow?No,she.She(sweep)thefloor.Ilike(play)theviolin.I'm(play)now.ButIcan't(dance).Doyoulike(peach)?No,I.Ilike(make)masks.Canyou(come)and(help)(he)with(he)Maths?they(sing)songsnow?Yes,they.Theycan(sing)many(song).What(be)intheschool?There(be)somebuildings.三.用现在进行时完成下列句子Whatyou(do)?I(sing)anEnglishsong.Whathe(mend)?He(mend)acar.you(fly)akite?Yes,.she(sit)intheboat?you(ask)questions?We(play)gamesnow.Whatareyou(do)now?I(eat)bread.It'snineo'clock.Myfather(work)intheoffice.Look,theboy(put)therubbishintothebin.he(clean)theclassroom?No,heisn't.He(play).WhereisMax?He(run)onthegrass.listen,who(sing)inthemusicroom?Oh,Mary(sing)there.he(talk)withme?We(play)footballnow.Whatyou(do)?I(sing)anEnglishsong.Theseboys(play)tennisontheplayground.Mymother(cook)inthekitchen.Wecan'thelpyou,becausewe(haw)classes.theboy(write)hishomework?Look!Thesebutterflies(fly)inthesky.Listen!Thegirl(sing)inthenextroom.Thenaughtyboy(swim)intheriver.一、用所给动词的适当形式填空Where'sourteacher? He(watch)afootballmatchontheplayground(操场)now.Don'tmakeanynoise.Jim(sleep)They(be)intheroomnow.Howcolditis!It's(snow)heavily.Listen!PeterandBecky(talk)abouttheweather.Bequiet!Myteacheris(say)something.It's8o'clock.They(have)anEnglishclass.Hurryup!Yourmother(wait)foryoudownstairs.(在楼下)Wherearethetwins? They(play)footballatschool.Mr.Jonescan'tcome.He(have)ameeting.Look!They(run)alongthestreet.We(practise)hardthesedaysbecausewewillhaveabigmatchnextmonth.you(study)English? Yes,Iam.用动词适当形式填空.Thepostman(send)aletternow.Helikes(he)job..Look,thatismylittlesister.She(read)(she)favouritebook..KittyandMissFang(look)atthemapoftheparknow..It's8o'clock.Peter(run)ontheParkRoad.Look,Kittyisbesidethepond.She(watch)thefishandtheducks.Haveyougot(some)apples?Yes,I'vegot(some).Whereare(they)friends?(they)areintheplayground.(not)openthewindow,please.It'scold.She(like)to(sing).Linda'smother(nothave)gotcoffee,butLinda(have).There(be)somejuiceinthebottle.There(be)fivebottlesofjuice.Canyouruncle(sing)verywell?Yes,heis(sing)now.Hercousins(like)(draw)pictures.Butnowthey(write)theirhomework.Wherearethepupils?They(have)lunchinthecanteen.Here(be)anyhayforthesmallcow.三、句型转换：Theyaredoinghousework.(分别改成一般疑问句和否定句)Thestudentsarecleaningtheclassroom.(改一般疑问句并作肯定和否定回答)'mplayingfootballintheplayground.(对划线部分进行提问)Tomisreadingbooksinhisstudy.(对划线部分进行提问)NancyiswatchingTVnow.(用everyevening替换now)6.1oftenlistentomusicintheevening.用now替often)四、现在进行时翻译练习.我正在读英语。IEnglish..他正在写字。He..你正在唱歌吗？是的，我在唱歌。不，我不在唱歌。you?Yes,./No,.他（她）在听音乐吗？he/she?.你正在干什么？我正在做作业。areyou?I'm..看！杰克正在游泳。Look,Jack..现在我正在打扫房间。Imynow..你父亲在干什么？他正在看电视。What yourfather ?He ..琳达经常在晚上做作业,但她今晚在看电视二Lindaoftenherintheevening.Butshethisevening.现在我们正在吃晚餐。Wenow.四、选择题Whoovertherenow?A.singingB.aresingC.issingingD.singIt'seighto'clock.ThestudentsanEnglishclass.A.haveB.havingC.ishavingD.arehavingListen!Thebabyinthenextroom.A.cryingB.criedC.iscryingD.criesLook!Thetwinsnewsweaters.A.arewearingB.wearingC.arewearD.iswearingDon'ttalkhere.Grandparents.A.issleepingB.aresleepingC.sleepingD.sleepTomisaworker.Heinafactory.Hissistersinahospital.A.work/workB.works/workC.work/worksWhoEnglishbestinyourclass?A.speakB.speaksC.speakingMrs.Readthewindowseveryday.A.iscleaningB.cleanC.cleansWemusicandoftentomusic.A.like/listenB.likes/listensC.like/arelisteningSheupatsixinthemorning.A.getB.getsC.gettingOnSundayshesometimeshisclothesandsometimessomeshopping.A.wash/doB.i