Unit1PastandpresentGrammar课件译林版八年级英语下册

Unit1PastandpresentGrammarLet'senjoyavideo.Eddie,haveyouseenmyfood?I'vejusteatenit.You'veeatenmyfood?You'vechanged,Eddie.You'vechangedtoo.Teachingaims1.能熟悉并能正确运用本课时的重点单词和短语。2.能掌握现在完成时的基本结构和用法。3.能掌握动词过去分词的变化规则。时间标志词——持续类判断现在完成时的核心依据，持续类表动作延续至今1.for+时间段：表动作持续的时长（for3years/foramonth）2.since+过去时间点/从句：表动作起始点（since2010/sincehecamehere）3.sofar/uptonow/untilnow：到目前为止（可放句首或句末）例句：WehavelearnedEnglishsince2019.Structureofthepresentperfecttensehave/has

+done

sb+

助动词

（可以帮助构成肯定、疑问和否定句）

动词的过去分词时间标志词——影响类影响类表过去动作对现在产生的结果/影响1.already：已经，仅用于肯定句，放助动词与过去分词之间2.just：刚刚，仅用于肯定句，位置同already3.yet：还（未），仅用于否定句/疑问句，放句末例句：Hehasjustleft./Haveyoufinishedtheworkyet?IhavelivedheresinceIwasborn.（presentperfecttense）Ilivedheretwoyearsago.（simplepasttense）

1.Weusethepresentperfecttensetotalkaboutanactionthatstartedinthepastandcontinuestothepresent.Usingthepresentperfecttense时间标志词——经历类经历类表过往的经历或动作发生的次数1.ever：曾经，仅用于疑问句，放助动词与过去分词之间2.never：从未，仅用于否定句，位置同ever3.before：以前，放句末；once/twice：一次/两次，表次数放句末例句：Haveyoueverswuminthesea?/Ihavebeentheretwice.

高频不规则动词（原形→过去分词）不规则变化需单独记忆，本单元核心必考：go→gone；see→seen；be→been；fall→fallencome→come；leave→left；do→done；find→foundforget→forgotten；eat→eaten；take→taken例句：IhavebeentoBeijing./Shehasgonetotheshop.重难点——延续性vs短暂性动词1.延续性动词：表可持续的动作/状态（live,have,keep,be）2.短暂性动词：表瞬间完成的动作，无法持续（leave,buy,borrow,join）核心规则：现在完成时接for/since表持续时，必须用延续性动词for

和since的用法:Theyhavehadthehousefor10years.=Theyhavehadthehousesince10yearsago.提问：Howlonghavetheyhadthehouse?1.for+段时间=since

+段时间+ago

现完2.提问：Howlong?动词过去分词——规则变化（2）3.辅音字母+y结尾：变y为i，再加-ed→carry→carried;study→studied4.重读闭音节（辅+元+辅）：双写末尾辅音，再加-ed→stop→stopped;plan→planned判断技巧：单词末尾只有一个辅音字母，且前面是单个元音字母，重读该音节HehasbeenawayfromBeijingforaweek.Hehashadacarsince2007.短动词长动词短动词长动词长短动词的转换：长短动词的转换短V长V开始(1)Thefilm______(begin)20minutesago.Thefilm_____________for20minutes

beganhasbeenon(2)Theparade__________(finish)hoursago.Theparade_____________forhours.结束/endfinishedhasbeenoverTip1:

短动词用一过，长动词用现完ReadandworkouttherulesHe’slivedtheresincehefinishedcollege.自从大学毕业以来，他就一直住在那里。居住在深圳的动作一直持续到现在pastpresenthavelivedthereWeusethepresentperfecttensetotalkabout:anactionthatstartedinthepastandcontinuestothepresent;（从过去持续到现在的动作或状态）;ReadandworkouttherulespastpresentIhave

lostmymobilephone.我的手机丢了anactionthathappenedinthepastandhasaconnectionwiththe______________(past,present);（动作发生在过去但对现在有一定的影响）;MymobilephonelostIdon'thaveaphone.present手机丢失导致我现在没有手机Whatarethechangesinyourhometown?HousingWeusedtoliveinsmallhouses,butmostfamilieshavemovedintonewbuildings.Whatarethechangesinyourhometown?CultureEnvironmentIndustryThequalityoflifeTransport长短动词的转换短V长V来/去/到Kitty_______HongKongtwodaysago.reached离开ShelefthomelastTuesday.长短动词的转换短V长V借Sheborrowedthisbooklastweek.HowlongcanI______(借)thisbook?keep买

buy

have/hashadIboughtthecarthreeyearsago.I__________thecar______threeyearsago.havehadsinceReadandworkouttherulesI’ve

beentoShenzhenthreetimes.我去过深圳三次。pastpresenthowmanytimesanactionhashappenedupto______________(thepresent,somepointinthefuture).（表示某个动作从过去到现在发生的次数）thepresentPairworkA:Hi!Longtimenosee.Iheardyouwentbacktoyourhometownlastmonth.Howwasthevisit?B:Oh,it’samazing!_____________________________________________.A:Wow,that’sgreat.Myhometownhaschangedalottoo.___________________________________________________________________________.B:Really?____________________________________________________.A:That’scool.Inmyhometown,__________________________________.B:Timesreallyhavechanged.Ithinkourhometownswillbecomeevenbetterinthefuture.A:Iagree.Ican’twaittogobackduringtheholidaytoseemorechanges!PresentperfecttenseFormthepastparticiplesofverbsWhentousethepresentperfecttense

FormthesentencestructuresTimeadverbialshave/has+donehave/has+not+doneHave/Has+subject+done...?Yes,subject+have/has.No,subject+haven’t/hasn’t.present

thepresent

ReadandworkouttherulesTheusagesofpresentperfecttense123从过去持续到现在的动作或状态表示某个动作从过去到现在发生的次数动作发生在过去但对现在有一定的影响presentthepresentTimeadverbials❀since+aspecifictime/+asentenceinthesimplepasttense❀

for

+aperiodoftime❀

over/inthe(past/last)years“在(过去的)这几年间”

❀

sofar,uptonow,until/tillnow“到目前为止”

❀already

“己经”“还(没)”“己经”

❀yet❀ever

“曾经”❀never

“从未”❀

just

“刚刚”❀recently

“最近”❀before

“以前”❀

timeadverbialsindicatingthenumberoftimes表示次数长短动词的转换短V长V加入/hasbeeninSimonjoinedtheFootballClublastyear.结婚AmarriedB15yearsago.=AandBgotmarried....=AgotmarriedtoB....Whendoweusethepresentperfecttense?1.for+一段时间

eg:forfivedays2.since+时间点/一般过去时的句子eg:sincelastSunday,sincehearrived3.just,already,yet,recently,over(thepast/last...)years,sofar,tillnow,untilnow,uptonow,bynow,4.ever,never,before5.Timeadverbialsindicatingthenumberof