初中现在完成时讲解

现在完成时,现在完成时:have/has+过去分词1)表示到现在为止已经完成或刚刚完成的动作。Nowwehaveplantedallthetrees.Hehasjustcomeback.,2)表示过去发生的动作,但强调结果或对现在的影响。Haveyouhadyoursupper?Ihavereadthebooktwicealready.在以上两种用法中常跟already,notyet,never,just,before,ever,recently等时间继续下去的状语。,3)表示过去已经开始,持续到现在,也许还会继续下去的动作或状态，常与包括现在在内的一段时间的状语连用。HehasstudiedEnglishfor6years.MaryhasbeenbusysinceshecamebackfromHangzhou.,过去分词的构成,1.直接加-ed。如：play-played2.以字母e结尾的直接加d。如：name-named3.以辅音字母加y结尾的，变y为i加ed。如：carry-carried4.重读闭音节且末尾只有一个辅音字母，双写这个辅音字母再加-ed。如：stop-stopped,现在完成时Presentperfect句型,1.肯定句现在完成时的肯定句式是“have（has）过去分词”。注意：该句式中的have或has是助动词，has用于第三人称单数，其它人称一律用have。2.疑问句现在完成时的一般疑问句式是把助动词have或has提到主语之前。（回答用“Yes，have（has）“No，havent（hasnt）”）3.否定句：现在完成时的否定句式是“havent（hasnt）过去分词”。,Ihaveeatenmylunch.,Shehaseatenherlunch.,Hehaseatenhislunch.,肯定句,Theyhaveeatentheirlunch.,Ihavenot(havent)seenthefilm.,Shehasnot(hasnt)seenthefilm.,现在完成时的否定形式：havenot(havent)+过去分词hasnot(hasnt)+过去分词,Ihaventeatensupper.eat-eatenHehasntchangedhisidea.change-changedMymotherhasne-come,否定句,Ivealreadyhaddinner.I_dinner_.2.Hehasjustfinishedhishomework.He_hishomework_.3.Mumscookedthedinner.Mum_thedinner.4.SusanslearnedEnglishatschool.Susan_Englishatschool.,havent,had,yet,hasnt,finished,yet,hasntcooked,hasnt,learned,把下列句子改为否定句,Haveyoueatenyourbreakfast?,现在完成时的一般疑问句形式Have/has提前+过去分词,HaveyouknownSandyforalongtime?Yes,Ihave/No,Ihavent.know-knownHassheeatenanythingsince9:00a.m.Yes,shehas/No,shehasnt.eat-eaten,疑问句,Ivealreadyhaddinner.2.Hehasjustfinishedhishomework.3.Mumscookedthedinner.4.SusanslearnedEnglishatschool.,Haveyoualreadyhaddinner?,Hashejustfinishedhishomework?,Hasmumcookedthedinner?,HasSusanlearnedEnglishatschool?,把下列句子改为一般疑问句,分清与一般过去时的用法现在完成时属于现在时态的范围，不能和表示过去的时间状语连用，如yesterday,lastnight,threeweeksago,in1990等.而一般过去时只表示过去的动作或状态，和现在不发生关系。eg-Ihaveseenthefilm.eg-Isawthefilmlastweek.eg-Hehaslivedheresince1993.eg-Helivedherein1993.,Notes:1)havegoneto与havebeentohavegoneto表示某人已离开了原地，去了另外某地，说话时，人已不在原地。后者表示某人曾havebeento去过某地，说话时人已不在某地了。HehasbeentoXiantwice.他曾经去过西安两次。（已经回来了）Youcantfindhim.HehasgonetoXian.你找不到他。他去西安了。（没回来）,动词填空：1._you_(clean)theroom?Yes,we_(do)thatalready.When_you_(do)it?We_(do)itanhourago.2._he_(see)thisfilmyet?Yes.When_he_(see)it?He_itlastweek.3.Howmanytimes_you_(come)here?Once.,Have,cleaned,havedone,did,do,did,Has,seen,did,see,saw,have,come,4.I_(read)thenoveltwice.Itsinteresting.5.She_(go)toPairs,hasntshe?Yes.How_she_(go)there?She_(go)therebyair.6.Sofar,manycountries_(develop)theirsoftwareprograms.7.MrChen_(give)upsmokinglastyear.8._youever_(ride)ahorse?Never.9.He_(keep)thebooksincetwodaysago.,haveread,hasgone,did,go,went,havedeveloped,gave,Have,ridden,haskept,Ivealreadyhaddinner.2.Hehasjustfinishedhishomework.3.Mumscookedthedinner.4.SusanslearnedEnglishatschool.,Whathaveyoualreadydone?,Whathashejustdone?,Whohascookedthedinner?,WherehasSusanlearnedEnglish?,对划线部分提问,（for+表示一段时间的词组，since+表示过去某一时刻的词或词组）谓语只可用延续性动词.,eg.-Ivelivedherefor15years.eg.-Ivelivedheresince15yearsago(1990),选用for和since填空:1.Wehaventseeneachother_alongtime.2.Hisfatherhasbeeninthefactory_10yearsago.3.Thefilmhasbeenon_20minutes.4.MrGreenhasworkedhere_hecametoChina.5.Hisgrandparentshavebeendead_severalyears.6.Itsfiveyears_wemetlasttime,for,since,for,since,for,since,练习题:1.Itsalongtimesincewe_(meet)last,isntit?2.-Iknowyou_(choose)apicturebookamongthese.-Yes,Havealookatit,please.3.Sofar,spaceshipswithoutpeople_(reach)themoonandsomeotherpartsoftheuniverse.4.Myfather_homeforn