现在完成时和过去完成时(1)现在完成时:1.概念:过去发生或已经完成的动作对现在造成的影响或结果,或从过去已经开始,持续到现在的动作或状态。2.时间状语:(时间标志词)thesedays,recently,lately,in/duringthepastfewyears,already,yet,never,ever,just,before,inthepast(last)fewdays,sofar,once,twice,for+时间段,since+过去的时间点,since+—般过去时的从句等。3.基本结构:have/has+done4.否定形式:have/has+not+done.5.一般疑问句:把have或has放于句首。6.反义疑问句:直接用has/have进行反问7.现在完成时的用法:①表示过去发生或已经完成的动作对现在造成的影响或产生的结果。如:—Haveyouhadyourlunchyet?你吃过午饭了吗?—Yes,Ihave.I'vejusthadit.是的,我刚吃过。(现在不饿了)Ihaveclosedthedoor.(门现在是关的)②表示从过去开始一直持续到现在的动作或状态,可能还要持续下去,常与for或since连用。表示持续的动作或状态多为延续性动词。如:Hehaslivedheresincel999.自从1999年以来,他就住在这儿。IhavelearntEnglishfortenyears.我学习英语有10年了。Wehavelivedherefortwoyears.(过去住到现在)8.难点:(1)现在完成时可和疑问词where,why,how连用,但不能和when连用.故现在完成时对时间的提问不用when,只用howlong。Wherehaveyoubeen?Whyhaveyouturnedofftheradio?Whenhaveyoucomeback?(×)HehasbeeninChinafor4years.(提问)When(×)/Howlong()hashebeeninChina?(2)havebeento/havegoneto/havebeenin的区别havebeento+地点表示曾经去过某地,现人已返回。(once,twice….)havegoneto+地点表示人已去了某地,人还未返回。(whereissb?)havebeenin+地点表示在某地呆多长时间。(for…../since…..)IhavebeentoBeijingtwice.–WhereisTom?–HehasgonetoHK.Lucyhasbeeninthisschoolfortwoyears.(3)短暂性动词和持续性动词的现在完成时A.若后面没有时间状语“for+时间段,since+时间点”时,短暂性和持续性动词都可用于现在完成时。如:Ihavebought(短暂)anewcomputer.()Hehasalreadylived(持续)inthesmallvillage.()B.若后面有时间状语“for+时间段,since+时间点”时,要用持续性动词或短暂性动词的否定。如:Theyhavestayed(持续)inthevillagefor10years.Ihavetaught(持续)Englishatthisschoolsince5yearsago.Youhaven’treceived(短暂)herletterfor2weeks.Wehaven’tleft(短暂)Chinasince20yearsago.注意:非延续性动词的否定形式可以与表示延续时间的状语连用。即动作不发生的状态是可以持续的。(错)Ihavereceivedhisletterforamonth.(对)Ihaven'treceivedhisletterforalmostamonth.C.短暂性动词的肯定不能与“for+时间段,since+时间点”连用,若要和他们连用则要将短暂性动词变为相对应的动词。如:Ihavecomeherefor3years.(×)→Ihavebeenherefor3years.()现举例说明这类动词的变化:下划线的词是错的,括号里的词是对的,borrow/lend→keptShehasborrowed(kept)themagazinesincetwoweeksago.catch→hadKatehascaught(had)acoldforoneday.buy→hadI’vebought(had)thisradiofor3years.puton→wornHehasputon(worn)thenewcoatforaweek.leave/go→beenawayTheyhaveleft(beenaway)foroneyear.start/begin→beenonThefilmhasbegun(beenon)for8minutes.getup→beenupHehasgoneup(beenup)morethantwohours.move→beenout(of)Jim’sfamilyhavemoved(beenoutof)hereforover2years.finish→beenoverThefootballmatchhasfinished(beenover)fortwohours.open→beenopenThefactoryhasopened(beenopen)since1990.close→beenclosedThefactoryhasclosed(beenclosed)for2months.die→beendeadThatoldmanhasdied(beendead)forthreeyears.join→beenin/beenamember(of)Herfatherhasjoined(beenin)thePartyfortenyears.come/become/arrive→been(in)Theyhavecometo(beenin)thisschoolsince1990.注意:非延续性(短暂性)动词的肯定不能与表示一段时间的状语连用。必须把非延续性动词改为相应的表示延续性的动词或短语,这时可与表示一段时间的状语连用。常见的非延续性动词通常作如下变换:come/goto→beat/in,leave→beawayfrom,buy→have,borrow/lend→keep,die→bedead,start/begin→beon,close→beclosed,open→beopen,join→bein/beamemberof/beasoldier.....,go/comethere→bethere,getmarried→bemarried,getup---beup,catchacold→haveacold,return→beback,fallill→beill,become→be,hasgoneto→hasbeenin,die---dead,makefriend---befriendfallasleep---beasleep,catchacold–haveacold,reach/get/arrive---stay/be等。误:lhaveboughtthiscomputerfortwoyears.正:Ihavehadthiscomputerfortwoyears.这台电脑我买了有两年了。(4)与现在完成时有关的四种句型之间的转换。现在完成时的四种句型:A).主语+短暂性动词的过去式+时间+agoB).主语+have/has+延续性动词的过去分词+for…./since….ago.C).It’s+时间段+since+短暂性动词的过去式D).时间段+haspassed+since+短暂性动词的过去式如:“我来广东有4年了”可用以下句型表示:IcametoGuangdong4yearsago.→IhavebeeninGuangdongfor4years.It’s4yearssinceIcametoGuangdong→FouryearshaspassedsinceIcametoGuangdong.Hisgrandfatherdiedtwoyearsago.Hisgrandfatherhas________fortwoyears._____twoyears_____hisgrandfather____.Twoyears____________hisgrandfather_____.(5)现在完成时与一般过去时的区别①.标志词不同(具体看两种时态标志词)如:Iwenttocinematwodaysago.(一般过去时标志词).Hehasbeenawaysincetendaysago.(现在完成时的标志词)②.一般过去时表示动作发生在过去,与现在无关。而现在完成时表示动作发生在过去,对现在造成影响。Isawthefilmyesterday.(我昨天看了这部电影)(强调看的动作发生过了)Ihaveseenthefilmbefore.(过去看过电影,强调对现在的影响,电影的内容已经知道了,不想再看了)Iwon’tseeitagain.Hashereturnedthelibrarybook?Yes,hehas.When____he_____(return)it?He____(return)ityesterdayafternoon.※句子中如有过去时的时间副词(如yesterday,last,week,in1960)时,不能使用现在完成时,要用过去时。(错)Tomhaswrittenalettertohisparentslastnight.(对)Tomwrotealettertohisparentslastnight.(6)用于现在完成时的句型1)Itisthefirst/secondtime....that…结构中的从句部分,用现在完成时。例如:ItisthefirsttimethatIhavevisitedthecity.这是我第一次访问这城市。Thisisthefirsttime(that)I'veheardhimsing.这是我第一次听他唱歌。注意:Itwasthethirdtimethattheboyhadbeenlate.2)Thisis+形容词最高级+that…结构,that从句要用现在完成时。例如:ThisisthebestfilmthatI've(ever)seen.这是我看过的最好的电影。(7)比较since和forSince用来说明动作起始时间,for用来说明动作延续时间长度。例如:Ihavelivedhereformorethantwentyyears.我住在这儿二十多年了。IhavelivedheresinceIwasborn.我从出生起就住在这儿了。注意:并非有for作为时间状语的句子都用现在完成时。Iworkedhereformorethantwentyyears.(我现在已不在这里工作。)Ihaveworkedhereformanyyears.(现在我仍在这里工作。)注意:用句型转换的方法,很容易排除非延续动词在有for/since结构的完成时中的误用。1)(对)TomhasstudiedRussianforthreeyears.=TombegantostudyRussianthreeyearsago,andisstillstudyingitnow.2)(错)Harryhasgotmarriedforsixyears.=Harrybegantogetmarriedsixyearsago,andisstillgettingmarriednow.显然,第二句不对,它应改为Harrygotmarriedsixyearsago.或Harryhasbeenmarriedforsixyears.拓展: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、1980,lastmonth,halfpastsix)