英语·选修8(人教版)第四学时Grammar语法精讲动词的时态和语态一、一般现在时的用法语法精讲1.表示经常性或习惯性的动作,常与表示频度的时间状语连用。时间状语有:always,often,never,sometimes,every,per,onSunday等。Ileavehomeforschoolat7everymorning.ShealwayswatchesTVonSundayevenings.2.表示客观真理,客观存在、科学的事实。Theearthmovesaroundthesun.ShanghailiesintheeastofChina.语法精讲注意:此用法如果出现在宾语从句中,即使主句是过去时,从句谓语时态要用一般现在时。Columbusprovedthattheearthisround.3.表示格言或警句。Pridegoesbeforeafall.骄者必败。Practicemakesperfect.熟能生巧。Hardworkleadstosuccess/Sussessliesinhardwork.4.现在时刻的状态、能力、性格、个性。Idon'twantsomuch.语法精讲Mr.WangwritesgoodEnglishbutdoesnotspeakwell.5.“be+介词+名词”结构,表示现在的状态,相当于现在进行时。Weareattable.=We'rehavingadinner.二、一般过去时的用法语法精讲1.一般过去时表示在确定的过去时间里所发生的动作或存在的状态。时间状语有:yesterday,lastweek,anhourago,theotherday,in1982等。Wheredidyougojustnow?2.表示在过去一段时间内,经常性或习惯性的动作。WhenIwasachild,Ioftenplayedfootballinthestreet.语法精讲3.wish,wonder,think,hope等用过去时,表试探性的询问、请求、建议等。Ithoughtyoumighthavesome.我以为你可能有一些。比较:一般过去时表示的动作或状态都已成为过去,现已不复存在。Mr.Greenusedtosmoke.(格林先生以前抽烟)Christinewasaninvalid(虚弱)allherlife.(她已不在人间)语法精讲Christinehasbeenaninvalidallherlife.(她现在还活着)Mrs.DarbylivedinKentuckyforsevenyears.(达比太太已不再住在肯塔基州)Mrs.DarbyhaslivedinKentuckyforsevenyears.(现在还住在肯塔基州,有可能指刚离去)语法精讲三、一般将来时的用法1.shall用于第一人称,will在陈述句中用于各人称。WhichparagraphshallIreadfirst?Willyoubeathomeatseventhisevening?2.“begoing+不定式”,表示将来。(1)主语的意图,即将做某事。Whatareyougoingtodotomorrow?(2)计划,安排要发生的事。Theplayisgoingtobeproducednextmonth.语法精讲(3)有迹象要发生的事。Lookatthedarkclouds,thereisgoingtobeastorm.3.“be+不定式”表将来,按计划或正式安排将发生的事。WearetodiscussthereportnextSaturday.4.“beabout+不定式”,意为“马上做某事”。HeisabouttoleaveforBeijing.注意:beaboutto不能与明确表示将来的时间状语连用。语法精讲begoingto/will用于条件句时,begoingto表将来,will表意愿。Ifyouaregoingtomakeajourney,you'dbettergetreadyforitassoonaspossible.如果你要去旅游的话,最好尽快做准备。Nowifyouwilltakeoffyourclothes,wewillfitthenewclothesonyou.如果你愿意脱下衣服的话,我们将给你试穿新衣服。语法精讲beto/begoingto:beto表示客观安排或受人指示而做某事。begoingto表示主观的打算或计划。Iamtoplayfootballtomorrowafternoon.(客观安排)I'mgoingtoplayfootballtomorrowafternoon.(主观安排)5.现在时表将来,常见的动词有want,hope,wish等Ihopetobeadmittedtoakeyuniversityin2016.TomorrowisFriday.语法精讲注意:(1)一般现在时表将来的用法。①下列短暂性动词:come,go,arrive,leave,start,begin,return的一般现在时表将来。这主要用来表示在时间上已确定或安排好的事情。Thetrainleavesatsixtomorrowmorning.—Whendoesthebusstart?—Itstartsintenminutes.②在时间或条件从句中。WhenBillcomes,askhimtowaitforme.I'llwritetoyouassoonasIarrivethere.语法精讲③在hope,takecarethat,makesurethat等后。Ihopetheyhaveanicetimenextweek.Makesurethatthewindowsareclosedbeforeyouleavetheroom.(2)用现在进行时表示将来,意为“意图”“打算”“安排”,常用于人。常用动词为come,go,start,arrive,leave,stay,die等。I'mleavingtomorrow.We'reflyingtoNewYorknextmonth.IhearoldBrownisdyingsoon.语法精讲四、过去将来时的用法过去将来时用来表示间接引用某人过去的话和想法,也表示过去某个习惯性的动作;在虚拟条件句中,表示非真实的动作或状态。有时还表示客气的请求或者说话者的某种愿望。Hewarnedusthatthetripwouldbeadventurous.(间接引语)Atdusk,theseoldmenwouldsitinrockingchairsandchatfreelyandhappily.(过去的习惯动作)语法精讲IfIwereyou,Iwouldnotlosethisgoodchance.(虚拟语气)Wouldyoumindhelpingmetofetchsomechalkfromtheoffice?Iwouldlikeacupofcoffee,please.(客气的请求)语法精讲五、现在完成时的用法1.现在完成时用来表示之前已发生或完成的动作或状态,其结果的确和现在有联系。动作或状态发生在过去,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。Myfatherhasworkedinthisuniversityfortwentyyears.(=Myfatherbegantoworkinthisuniversitytwentyyearsago,andheisstillworkinghere.)语法精讲2.用于现在完成时的句型。(1)Itisthefirst/secondtime...that...,结构中的从句部分的谓语用完成时。ItisthefirsttimethatIhavevisitedthecity.Itwasthethirdtimethattheboyhadbeenlate.(2)Thisisthe...that...结构,that从句要用现在完成时。ThisisthebestfilmthatI've(ever)seen.语法精讲3.比较since和for:since用来说明动作起始时间,for用来说明动作延续时间的长度。Ihavelivedhereformorethantwentyyears.IhavelivedheresinceIwasborn.IhaveknownXiaoLisinceshewasalittlegirl.MybrotherhasbeenintheYouthLeaguefortwoyears.4.since的四种用法。(1)since+过去一个时间点(如具体的年、月、日期、钟点,如1980,lastmonth,halfpastsix)。语法精讲Ihavebeenheresince1989.(2)since+一段时间+ago。Ihavebeenheresincefivemonthsago.(3)since+从句。Greatchangeshavetakenplacesinceyouleft.(4)Itis+一段时间+since从句。ItistwoyearssinceIbecameastudenthere.Itisfiveweekssincehewasmarriedtoher.语法精讲现在完成时常用的信息词:sofar,bynow,overtime,since+过去时间,since+一段时间+ago,recently,lately,tillnow,inthepast/last/recent+时间名词,bytheendof+现在时间。语法精讲六、过去完成时的用法1.概念:表示过去的过去,其构成是“had+过去分词”。2.用法。(1)在told,said,knew,heard,thought等动词后的宾语从句中。Shesaid(that)shehadneverbeentoParis.(2)在过去不同时间内发生的两个动作中,其中发生在先的动作用过去完成时;发生在后的,用一般过去时。语法精讲Before/Whenthepolicearrived,thethieveshadrunaway.(3)表示意向的动词,如hope,wish,expect,think,intend,mean,suppose等,用过去完成时表示“原本……,未能……”。Wehadhopedthatyouwouldcome,butyoudidn't.3.过去完成时的时间状语:before,by,until,when,after,once,assoonas。HesaidthathehadlearnedsomeEnglishbefore.语法精讲Bythetimehewastwelve,Edisonhadbeguntomakealivingbyhimself.Tomwasdisappointedthatmostoftheguestshadleftwhenhearrivedattheparty.ThestudentswerewritingbusilywhenMissBrownwenttogetabookshehadleftintheoffice.注意:用一般过去时代替完成时的用法:(1)叙述历史事实,可不用过去完成时,而只用一般过去时。语法精讲OurteachertoldusthatColumbusdiscoveredAmericain1492.(2)句中有before,after时用一般过去时代替过去完成时。He(had)studiedmathsfromhisbrotherbeforehewenttoschool.Afterhe(had)finishedhiswork,oldTomwenttosleep.语法精讲七、将来完成时的用法1.构成:willhavedonesth.。2.概念。(1)状态完成:表示某事继续到将来某时为止一直具有的状态。(2)动作完成:表示将来某时或另一个将来的动作之前,已经完成的动作或获得的经验。Theywillhavebeenmarriedfor20yearsby2013.Y