1现在完成时现在完成时( PresentPresent PerfectPerfect TenseTense)现在完成时是初中英语中最重要也最难掌握的一个时态，同时也是中考英语中一个最重要的时态考点. 一、 基本结构：“have / has+过去分词”(一)肯定句：主语have /has + PP I have already had lunch.否定句：主语havent /hasnt +PP I havent had lunch yet.疑问句： Have/Has +主语+ PP. Have you had lunch yet?回答： Yes ,主语+ have /has. No, 主语+ havent /hasnt.（二）总结：1.、谓语:_have / has 为助动词，助动词说明该谓语是属于现在时范围。它和主语的人称、数要保持一致。过去分词是主要的谓语动词，说明句子的意义。2、构成疑问句时，_；构成否定句时，_。(三)动词过去分词1）规则变化：+ed. playede 结尾+d. skated辅音字母+y 结尾 改 y 为 i + ed. studied 双写最后一字母+ed. stopped ,preferred（以重读闭音节或 r 音节结尾且末尾只有一个辅音字母动词）2）不规则变化：背、做练习二、标志： already (否定 yet) ever (否定 never) just before for+段时间 since+点时间 so far twice，many times 等数词三、用法现在完成时主要有两种用法，一种是已完成用法，也叫影响性用法；另一种是未完成用法，也叫持续性用法。两种用法的特点是：1） 影响性用法：表示过去发生或已完成的动作对现在造成的影响，强调的是影响。这个动作在过去已经完成， 这个动作对现在有影响，常与 already, yet（仍，还没，用于否定和疑问句），ever, never，the (last/past) few (years/days)，before，just 等连用。eg. I have already read this story.（对现在 的影响或结果：我已经知道故事的内容）动词过去分词2-Have you had lunch yet? -Yes, I have. Ive just had it.你（已经）吃午饭了吗？ 我刚刚吃过。（现在我不饿了）He has never driven a car before. 他过去从未开过车。Our hometown has changed a lot in the past few years. 我们家乡在过去的几年里变化很大。Have you ever been a teacher？ 你当过教师吗？already（”已经” 用于肯定句的中间和末尾处）never (“从不” 用于中间处)ever （”曾经” 用于疑问句和肯定句的中间处）just (“刚刚” 用于中间处)yet (“已经” 用于疑问句的末尾处 / “还” 用于否定句的末尾处)练习：( )1.Have you traveled on the train. Yes, I have.(A)never (B)ever (C)just (D)yet( )2.Have you finished your homework Not .(A)ever (B)already (C)yet (D)just( )3. We havent finished our homework .(A)already (B)ever (C)yet (D)never( )4.Have you learned English?Yes, Ive learned a lot.(A)never, ever(B)ever, never(C)ever, already (D)already. ever( )5.Have you finished your homework ?Yes, Ive done that (A)yet, already (B)already, yet (C)ever, never (D)still, just( )6.Johns father borrowed some pictures(A)have already （B)has just (C)have ever (D)has yet( )7.He finished his homework yet(A)doesnt (B)havent (C) hasnt (D) doesnt havejust ,just now：刚刚just ,“刚刚,恰好”，常用于现在完成时，放在句中。Ive just had lunch.just now,“刚才”，常用于一般过去时，放在句末。I had lunch just now.2） 持续性用法：表示过去已经开始的某一动作或状态一直持续到现在，可能还会持续下去。从过去持续到现在 ，常有下列标志：for+for+时间段时间段3（ten years, a long time 等）；since+since+时间点时间点（two oclock, August 2003,I came here, two days ago 等）；recentlyrecently，soso far,far, upup toto nownow 等Eg.We have studied English for over 6 years.I havent seen her since last week.How have you been？ 你近来怎样？I have been very tired recently.How long have you been in Shanghai？ 你在上海已经多久了？since ,for 用于完成时态，since 用来说明动作起始时间，for 用来说明动作延续时间长度，时间点即你能够指出一个确切的时间。1) since+时间点：Lucy has lived there there since 1955.since+时间段+ago:I have been teaching since 10 years ago.since+一般过去时的句子：We have known each other since we were young.2) for+时间段：We have studied English for over 6 years.练习：1、用 since 和 for 填空（用画线段的方法）1) _ two years2) _ two years ago3) _ last month 4) _ 19995) _ yesterday6) _ 4 oclock7) _ 4 hours8) _ an hour ago9) _ we were children 10) _ lunch time11) _ she left here have been to,have gone to, have been in 的区别have been to：曾经去过某地（已返回），通常可与表示次数的状语连用。Have you ever been to Shanghai?Yes.I have been to shanghai twice.have gone to:去了某地（还没回来）Where is Lucy? She has gone to the lab.have been in:去到或来到（一直呆在那儿）+一段时间练习： 1、Susan isnt here now. She _ to England. She will come back next month.A. will go B. has gone C. goes D. went 2、How long _Korean singer Jang Nara _China?Four years. She can speak and sing in Chinese. A. does; go to B./; was in C. has; been to D. has; been in 3、Hello! Can I speak to Alice?Sorry she isnt here right now. She_ to the shop.since+较为较为具体的时间具体的时间4A. goes B. will go C. has gone D. was going 4、They_ China for two years . Ahave been to B.have been in c.have gone to D.have come to5、I _never _ England.A.have;been to B.have; gone to C. have;been in D.has; been in注注：1 1.除以上用法外，现在完成时还可表示过去到现在重复的过去到现在重复的动作在时间或者条件状语从句时间或者条件状语从句中还可表示将来动作将来动作。如：He has always gone to work by bike. 他总是骑自行车上班。Ill go to bed when Ive finished my homework. 我做完作业后就上床睡觉。2.2.表示时间长度时，通常通常用一般现在时代替现在完成时。It is +时间段+since+一般过去时态的句子。如：Its a long time since I met you last. 好久不见了。Its about six months since we arrived here. 我们到这里大约有半年了。3 3、表示“第几次做某事，”或在 “It is the best (worst, most interesting ) +名词that” 后面用现在完成时。This is my first time that I have visited China. That is the only book that he has written.This is the most interesting film I have ever seen.典型考例典型考例： 1）How long _ you _ England, Sue?Since two years ago.A. have, been to B. have, gone to C. have, been in D. have, moved to2）It _ two years since he _