现在完成时定义：1.表示过去发生或已经完成的动作对现在造成的影响或结果。

2.也可以表示过去已经开始，一直延续到现在的动作或状态现在完成时的结构have/has+ done ()如：I have lived here for more than thirty years.我已在此住了30多年。

现在完成时的时间状语ever, never, twice（once…）, so far（到目前为止）, , already（肯定句）,yet（否定，疑问句）, just(刚刚), before（以前）, recently（近来）等词连用2.Since+时间点，for+时间段，in the past/last few years说明：already与yet都有“已经”的意思，但already常用于肯定句，并用于句中。

yet常用于否定句和疑问句，并用于句末。

例如：I have already finished my homework.I haven't finished my homework yet. Have you finished your homework yet?They have left. (他们已经离开了,也就是说现在他们人不在这里)I have had my lunch. (我已经吃过午饭了,也就是说我现在不饿)I can't find my watch now. I think I have already lost it.注意：1)现在完成时不能单独与过去的时间状语连用, 如yesterday, lastweek, three years ago 等; 2)不能与when连用现在完成时的用法1 / 12A．表示过去发生或已经完成的动作对现在造成的影响或结果，强调对现在造成的影想或结果）。

例如：The car has arrived.车子来了。

（结果：车子已在门口）Someone has broken the window.有人把窗户打破了。

（结果：窗户仍破着）B. 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（包括“现在”在内）的一段时间的状语连用,如for+时间段、since+过去的时间点、疑问词how long等。

例如：My uncle has worked at this factory for five years. 我叔叔在这个工厂工作已经五年了。

Mr. Black has lived in since 2002. 自从____年Mr. Black 一直住在xx。

How long have you been here? 你来这里多久了？用相应的延续性动词替换短暂性动词，句中谓语动词用现在完成时，时间状语为“for＋时间段”或“since＋时间点”。

如：He has been in the Green China for three years.He has been a member of the Green China for three years.他加入“绿色xx”已经三年了。

The old man died 4 years ago.---- The old man has been dead for 4 years. He joined the Party 2 years ago.---- He has been in the Party for 2 years.I bought the book 5 days ago.---- I have had the book for 5 days.表示时间段的短语有:for+一段时间(for 2 years), since+从句(since he came here), since+时间点名词( since last year, since 5 days ago),how long; for a long time等。

现在完成时态与一般过去时态的区别2 / 121一般过去时表示过去某时发生的动作或单纯叙述过去的事情，强调动作；现在完成时为过去发生的，强调过去的事情对现在的影响，强调的是影响。

I saw this film yesterday.（强调动作发生的时间是yesterday 。

）I have seen this film.（强调对现在的影响，电影的内容已经知道了。

）2一般过去时和表示过去的时间状语连用，如：…ago, last week/...in 2008, in the past, just now, the day before yesterday,yesterday ..then(那时),that day, one day, once(从前)现在完成时常和recently（近来），ever, never, twice, so far（到目前为止）, since，for，in the past/last few years , already（肯定句）, yet（否定，疑问句）, just(刚刚), before（以前）连用。

现在完成时不与表示过去的时间状语连用。

现在完成时可表示持续到现在的动作或状态，动词一般是延续性的，如live, teach, learn, work, study, know.比较have/has been to、have/has gone to 和have been inhave(has) been to...表示“曾去过某地，已经从那里回来了”，可以和ever、never、twice等连用。

have(has) gone to表示“已经去了某地，在去那里的途中或到达那里还没有回来”。

have(has) been in 表示“在某地呆多长时间”，常与表示一段时间的状语连用，如：since, for, how long 等He went to Shanghai last week 上周他去了xxHe has been to . 他(曾经)到/去过xx.(但他人现在肯定不是在xx而是回来了)He has gone to Shanghai.他已经去xx了.(也许刚动身出发,也许已经到了,也许还在路上,反正他人不在这里)Mr. Brown has been in for three days. xx先生来xx已经有三天了3 / 12六．过去分词1 、规则动词：规则动词的过去分词的构成规则与规则动词的过去式的构成规则相同。

四点变化规则：(1)、一般动词，在词尾直接加“ed ”。

work---worked---worked ,visit---visited---visited(2)、以“e ”结尾的动词，只在词尾加“d ”。

live---lived---lived ,(3)、以“辅音字母+ y ”结尾的动词，将y 变为i ，再加“ed ”。

study---studied---studied ,cry---cried---cried(4)、重读闭音节结尾，末尾只有一个辅音字母，先双写该辅音字母，再加“ed ”。

stop---stopped---stopped , drop---dropped--dropped2 、：AAA型burst burst burst hurt hurt hurt let let letcast cast castcost cost cost cut cut cuthit hit hitput put putshut shut shut spread spread spreadset set setread read read read原形发音为/ri:d/,过去式和过去分词发音为/red/AAB型beat beat beaten特殊情况ABB型bring brought brought buy bought bought build built built4 / 12burn burnt burntcatch caught caught dig dug dugfeel felt feltfight fought fought find found foundhear heard heardhold held heldkeep kept keptlay laid laidlead led ledlose lost lostmake made made meet met metsell sold soldshoot shot shotsit sat satstand stood stoodsweep swept swept teach taught taught tell told toldthink thought thought win won wonABC型begin began begun blow blew blownbreak broke brokenchoose chose chosen draw drew drawndrive drove drivendrink drank drunkfly flew flownforgive forgave forgivenforget forgot forgotten freeze froze frozen give gave givengrow grew grownknow knew known ride rode riddenrise rose risenring rang rungshake shook shakensing sang sungsink sank sunkswim swam swumthrow threw thrown write wrote writtenbuy----haveborrow -----keepgo out----be out begin-----be onopen----be openclose -----be closeddie----be dead★1.have代替buyMy brother has had(不能用has bought) this bike for almost four years.5 / 122、用keep或have代替borrowI have kept(不能用have borrowed) the book for quite a few days. How long has your sister been a teacher?4、用have a cold代替catch a coldTom has had a cold since the day before yesterday.5、用wear代替put onb)用“be＋形容词”代1、be＋married代marry2、be＋ill代fall (get) ill3、be＋dead代die4、be＋asleep代fall (get) asleep5、be＋awake代wake/wake up6、be＋gone代lose,die,sell,leave7、be＋open代open8、be closed代close/shut9、be＋missing(gone,lost)代losec)用“be＋副词”代终止性动词1“be＋on”代start, begin2“be＋up”代get upd)用“be＋介词短语”代终止性动词3.“be in/at +地点”代替move to常用瞬间动词变表：6 / 12→have been in sw./at…相应的介词6. have got up →have been up；7. have died →have been dead；8. have left sw. →have been away from sw.9. have fallen asleep/got to sleep →have been asleep；11. have married →have been married；12. have started/begun to do sth. →have done sth. ；13. have begun →have been on14. have borrowed/bought →have kept/had15. have lost →haven't had16. have put on →have worn17. have caught /get a cold →have had a cold；18. have got to know →haveknown19. have/has gone to →have been in20. have joined/have taken part in the league/the Party/the army→have been a member of/ have been in/ have been the Party's member/现在完成时练习（一）一、用过去时或现在完成时填空：1. “_________ you __________ (have) lunch ?”“Yes.”“When ________ you __________ (have) it?”“I ____________ (have) it at12:00.”2. “_________ you __________ (write) a letter to your aunt yet?”“Yes, I ___________. I ________________ (write) one last week.”3. “_________ he ___________ (finish) his homework?”“Not yet.”4. “_________ they ever __________ (be) abroad?”“Yes, just once.”7 / 125. Your father _________ just ___________ (finish) his work.6. Your father _________ (finish) his work just now.7. Last term I __________ (learn) many English words.8. They ____________ (not read) the interesting books yet.9. He _____________ never ____________ (go) to the science museum.10. ____________ you ever ____________ (drink) coke?11.Have you _____________ (buy) a dictionary? ““Yes, I __________ .”“Where______ you ___________(buy) it?”“I _________(buy) it in a bookstore.”“When ___________ you _____________ (buy) it?”“Yesterday.”单项选择。