会计学现在完成时:have/has+过去分词1)表示到现在为止(wéizhǐ)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(yǐshàng)两种用法中常跟already,not…yet,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(dòngzuò)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(gòuchéng)现在完成(wánchéng)时Presentperfect句型Ihavenot(haven’t)seenthefilm.I’vealreadyhaddinner.I________________dinner________.2.Hehasjustfinishedhishomework.He________________hishomework_________.3.Mum’scookedthedinner.Mum_______________thedinner.4.Susan’slearnedEnglishatschool.Susan________________Englishatschool.Haveyoueatenyourbreakfast?I’vealreadyhaddinner.2.Hehasjustfinishedhishomework.3.Mum’scookedthedinner.4.Susan’slearnedEnglishatschool.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(fànwéi)，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(shírén)已不在某地了。HehasbeentoXi‘antwice.他曾经去过西安两次。（已经回来了）Youcan’tfindhim.HehasgonetoXian.你找不到他。他去西安了。（没回来）动词(dòngcí)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.4.I_______(read)thenoveltwice.It’sinteresting.5.She_______(go)toPairs,hasn’tshe?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.I’vealreadyhaddinner.2.Hehasjustfinishedhishomework.3.Mum’scookedthedinner..4.Susan’slearnedEnglishatschool.（