现在完成时的基本句型：肯定式：主语+助动词have/has +动词的过去分词.疑问式：助动词Have/Has +主语+动词的过去分词？ 否定式：主语+助动词have/has + not +动词的过去分词.例句：1. I have cleaned my room. 我已打扫了房 间2. He hasn't finished his homework.他还没完成作业3. Have you read this novel ?你看过这本小说吗？Yes , I have.是的，看过了No, I haven't.不，没看过4. We have studied English for two years.我们已经学了两年英语了5. They haven't seen each other since 1998.自从1998年他们就没再见过面现在完成时的主要用法1 •表示过去发生的某一动作对现在造成的影响或结果Ifs so dark.—Someone has turned off the light.（有人刚把灯关了,对现在造成的结果是:现在很黑）— Are you free?—I have finished my homework. I am free（我已经完成了家庭作业，对现在造成的结果是很有空）2•表示过去已经开始，持续到现在的动作或状态，可以和表示从过去某一 时刻延续到现在的一段时间的状语连用•表示持续动作或状态的词应是 延续性动词•常与since +过去的时间点，since+谓语是一般过去时的从 句；for+ 一段时间，so far等时间状语连用。
如：I have learnt English for more than ten years.我 已经学了 10 多年的英语 （从10年前开始,持续到现在还在学）She has swum since half an hour ago.我已经游泳 了 半个小时（半个小时前已经开始游泳，到现在还在游）3 •表示人曾有过或到目前为止从未有过的经历.I have ever been to the Summer Palace?（我曾去过颐和园）I have never had a car.（我从未有过汽车现在完成时的时间状语常与① already,②never,③ever,④just （刚才），⑤yet, ©before, ©up to now,⑧so fai•（到目前为止），®for the last few weeks,⑩these days, ODsince 2010/ two years ago, since he came here, OZ）for a long time （13） in the last/ past*••years 等连用a） already往往用于肯定句，用在疑问句时表示强调或加强语气;yet用 于否定句和疑问句。
eg:• He has already left here.他已经离开这里了• Has he already left here?他（真的）已经离开这里了吗？（表示加强语气）• My teachers haven71 had breakfast yet.我的老师们还没有吃早饭• Have you written to your parents yet?你已经给你父母写过信了 吗？b） nevei■是否定词，表示“从来没有”，而evei•表示“曾经”• We have never been to the Great Wall.我们从来没有去过长城• Have you ever been to Canada? 你们曾经去过加拿大吗？c） just表示“刚刚”（用于完成时态时，与already, never等副词的位 置一样，多用在助动词have/has和动词过去分词之间）Just now（用于 过去时）• He has just come back.他刚刚回来• They have just finished the work.他们刚刚完成那项工作d） before用于完成时，而ago用于过去时• He has started his work ten years before.他十年前就已经开始他的工作了。
• He started his work ten years ago.他是十年前开始他的工作的常用于现在完成时的时间副词,介词：already （已经）：用于肯定句 I have already posted the letter . yet（已经）：用于否定句,疑问句 He hasn't done his homework yet. just（刚刚）They have just left.ever（曾经）Have you ever been to Beijing ?never（从不）I have never seen him . before（以前）Have you seen the film before?since（自从…以来）I've worked in the school since 1999.for（长达）He's lived in Shenzhen for 6 years.in the past several days / weeks/ years（在过去的...） recently（最近）I have not written to my parents recently.so far（至目 前为止） So far she has learned 5 English songs, up to now（至I」目前为止）this morning/month/year（今天早上/这个月/今年）现在完成时与一般过去时的区别I lived there 2 years agoI have lived here for two yearsI have lived here since two years ago.I have lived here since I came here.1. 都表2K过去发生的事2. 现在完成时强调过去和现在的联系，不能和具体的时间状语连用；3. —般过去时强调过去发生的事或状态与表示过去的具体时间连用（last, ago, yesterday, etc.）当有一个表示过去某时的状语时，不能用现在完成时，而多用一般过去 时。
I saw Mary an hour ago.She lost her handbag yesterday ・有些时间状语，既能用于现在完成时，又能用于一般过去时，但意义上 有差别Fve written three letters this morning.（说话时仍是上午）I wrote three letters this morning.（说话时仍是上午或晚上）现在完成时强调动作或事情发生在过去，一直延续到现在，而且还有可 能继续延续下去；而一般过去时只表示发生在过去的动作或事情I have taught this class for ten years.（还在教）I taught this class for two years.（曾教过两年，现在不教了）一般过去时态和现在完成时态同义转换1•我们买这本书三年了.We have had the book for three years.We bought the book three years ago.2. 他感冒三天了.He has had a cold for three days.He caught a cold three days ago.3. 我借的这本书一周多了.I have kept the book for a week ・I borrowed the book a week ago.4. 我成为一个学生两年多了.I have been a student for over two years.I became a student two years ago.5. Mr Black 死了三年了。
Mr Black has been dead for three years.Mr Black died three years ago.重点句型：It is/has 时丽从句 段时 丽刀俯passed^ since 从句eg.他去世了两年了 ：He died two years ago.He has been dead for two years /since two years agoIt is/ has been two years since he died.Two years has passed since he died.注：现在完成时不能和表示过去的时间状语如：yesterday, last year, in 1980,three days ago, just now, when I came in等连用Pay attention注意不能是具体过去时间1 •现在完成时句中常见的时间状语A・表示从过去一直持续到现在，不能是具体过去时间B.just,already,yet,before/ ever,never有此类副词时，常强调动作完成，不 强调动作的持续.eg・ Have you ever been to Japan?I have just finished my homework.I have finished my homework already.I haven9t finished my homework yet2 •区分短暂性动词与持续性动词.英语的行为动词大体可以分为两大类型：一是延续性的动词，二 是短暂性动词。
延续狂动词是指那些动作意义不会一下完成，而是可以 延续、发展的动词如：work・read・write.stiidv等.短暂性动词^指那些 动作一次完成，不能延续的动词如：come, go, buy, die, borrow,begin 等表示短暂性（瞬间性）的动词在现在完成时的句中不能和一段时间连 用•即for,since短语或 how long问句I have bought this pen for two months.（错）I have had this pen for two months. （正确） How long have you had this pen.? （正确）The play has begun for an hour. (错)The play has been on for an hour. (正确)结束性动词不能和表示一段时间的时间状语连用，但是他可以转换成相 应的延续性动词.1 •直接用延续性动词buy- have catch(get) a cold -have a cold borrow―keepcome/go /become—be put on- wear2 •转换成be+名词join the army -be a soldier join the Party -be a Party membergo to school- be a student3转换成be+形容词或副词die―be dead finish - be over begin—be on open―be openleave―be away (from- • •) fall sl。