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1、Unit8HaveyoureadTreasureIslandyet?SectionAGrammarFocusGrammarFocusHaveyoureadLittleWomenyet?Yes,Ihave./No,Ihaven't.HasTinareadTreasureIslandyet?Yes,shehas.Shethinksit'sfantastic.Haveyoudecidedwhichbooktowriteaboutyet?Yes,Ihave.I'vealreadyfinishedreadingit.Itwasreallyg
2、ood.现在完成时态 presentperfect现在完成时：表示过去发生或已经完成的某一动作对现在造成的影响或结果，或从过去开始一直延续到现在的动作或保存的状态。结构：主语+have/has+动词的过去分词一般疑问句：have/has…?Yes,Ihave.No,Ihaven’t.Yes,shehas.No,shehasn’t.1.现在完成时动词构成have/has+v过去分词助动词否定haven’thasn’t疑问Haveyou…?Hashe…?常与下列时间状语连用：just,already,yet,ever,never,be
3、fore,severaltimes现在完成时1.过去发生的动作对现在造成的影响或结果。和already，never,ever,just,before,yet等状语连用。2.过去已经开始，持续到现在的动作或状态，常与for或since引起的一段时间状语连用。动词构成：have/has+v过去分词havebreakfastIhavejusthadmybreakfast.(现在我不饿)I’mnothungrynowmovedherein2004IstilllivehereIhavelivedhereforthreeyears.Ihave
4、livedheresince2004/threeyearsago.nowpast2.现在完成时动词可以表示开始于过去持续到现在(也许还会继续进行下去)的动作或状态。1)IhavestudiedEnglishsincelastyear.我从去年开始学习英语。2)ShehaslivedinBeijingforfiveyears.她住在北京已经五年了。注意:come,go,leave,arrive,buy,lose,receive,join,die,bury和marry等动词所表示的动作是一时的,不能延续的,故不能与for…,since
5、…等开头的表示一段时间的状语连用。不过,这些词用于否定句则可以与表示持续的时间状语连用，即动作的不发生是可以持续的。不能说:*HehascometoBeijingfortwoyears.*Hehasboughtthatbookforthreeweeks.*HehasjoinedtheArmyforoneandahalfyears.*Hisgrandmahasdiedforninemonths.*Ihavereceivedhisletterforamonth.可以说:HehasbeeninBeijingfortwoyears.Heh
6、ashadthatbookforthreeweeks.Hehasbeeninthearmyforoneandahalfyears.Hisgrandmahasbeendeadforninemonths.Ihaven'treceivedhisletterforalmostamonth.或者说：ItistwoyearssincehecametoBeijing.Itisthreeweekssinceheboughtthatbook.ItisoneandahalfyearssincehejoinedtheArmy.Itisninemonth
7、ssincehisgrandmadied.3.现在完成时把过去的动作和现在的结果联系起来，一般过去时只限于表示过去的动作本身,与现在的结果无关。现在完成时与一般过去时在意义上的区别举例如下：Ihavecleanedmyroom.(Myroomiscleannow.)我已经打扫过我的房间了。Icleanedmyroomlastweek.(Ididitinthepast.)我上周打扫了我的房间。FatherhasgonetoAmoy.(HewenttoAmoyandheisnotherenow.)爸爸已经去厦门了。Theyhavebo
8、ughtadictionary.(Theyboughtadictionaryandtheyhaveitnow.)他们买了一本字典。注意:现在完成时不能和明确指出时间的状语(如:yesterday,last,year,in1976,twodaysag
