八年级下英语现在完成时讲解及练习

现在完成时一、现在完成时态的结构have /has (助动词)+done(过去分词)说明：动词的过去分词有规则形式和非规则形式两种，规则形式同过去式的规则形式。

非规则形式需要特殊记忆。

可以这样分类：AAA、ABB、ABA、ABCAAA cost-cost-cost，hit-hit-hit，let-let-let，put-put-put，set-set-setABB buy-bought-bought，catch-caught-caught，find-found-found，stand-stood-stoodABA come-came-come，become-became-becomeABC break-broke-broken，fly-flew-flown，take-took-taken，write-wrote-written二、现在完成时态的基本句式肯定句：主语+have/has+其他否定句：在助动词have/has后加上否定词not一般疑问句：将助动词have或has提到句首，肯定的简略回答是：Yes，主语＋have/has. 否定的简略回答是：No，主语＋have/has not.特殊疑问句：特殊疑问词+一般疑问句三、现在完成时态的用法1、用来表示之前已经发生或完成的动作或状态，而其结果却和现在有联系: 动作或状态发生在过去,但它的影响现在还存在,可以和already, never, ever, just, before, yet等副词连用。

例如：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. (丢手表发生在过去，但现在还没有找到，即过去的动作对现在造成的影响。

)He has seen the film. So he won’t go with us. (看电影发生在过去，但现在仍然记得它的内容。

) 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 have n’t finished my homework yet. Have you finished your homework yet?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（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 China since 2002. 自从2002年Mr. Black 一直住在中国。

How long have you been here? 你来这里多久了？注意：此种用法中表示持续动作或状态的动词必须是延续性动词（否定句除外）。

例如：(1)这本书我已经买了三个月了。

错误：I have bought the book for three months.正确：I have had the book for three months.(2)你哥哥参军多长时间了？错误：How long has your brother joined the army?正确：How long has your brother been in the army/been a soldier?四、现在完成时态与一般过去时态的区别1一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.（强调看的动作发生过了。

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

）2一般过去时常与具体的表示过去的时间状语连用;现在完成时通常与模糊的时间状语连用，或无时间状语。

一般过去时的时间状语: yesterday,last week, ago,in1990,in October,just now,现在完成时的时间状语:for,since,so far,ever,never,just, yet,till/until,up to now,in the past few years,recently句子中如有过去时的时间副词（如 yesterday, last, week, in 1960）时，不能使用现在完成时，要用过去时（错）Tom has written a letter to his parents last night.（对）Tom wrote a letter to his parents last night.3）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.一般过去时常用的非持续性动词有come, go, leave, start, die, finish, become, get married等。

She joined the League three years ago. (加入的动作不是延续的)She has been in the League for three years (since three years ago). (在团内的状态可延续) She has been a League member for three years (since three years ago).是团员的状态可持续) 比较since和forsince 用来说明动作起始时间—“自从……”,for用来说明动作延续时间长度—“长达……”。

在有for 和since 引导时间状语的句子中不能用短暂性动词，应用与之相应的表示状态的词I have lived here for more than twenty years.I have lived here since I was born.My aunt has worked in a company since 1949.I have not heard from my uncle for a long time.注意：并非有for 作为时间状语的句子都用现在完成时I worked here for more than twenty years. (我现在已不在这里工作。

)I have worked here for many years. (现在我仍在这里工作。

)比较 have/has been to、have/has gone to 和 have been inhave(has) been 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 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[注意]：第三人称”。

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 上周他去了上海He has been to Shanghai. 他(曾经)到/去过上海.(但他人现在肯定不是在上海而是回来了)He has gone to Shanghai. 他已经去上海了.(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 Shanghai for three days. 布朗先生来上海已经有三天了延续性动词和瞬间性动词之间的转化1.He died 10 years ago. ——He ______________ for 10 years / since 10years ago.2. He borrowed the book 2 weeks ago. ——He _____________the book for 2 weeks.3. He bought the motorbike a month ago. ——He ___________the motorbike for a month.4. He arrived here three days ago.——He ____________here since three days ago.5. They turned off the light 2 hours ago. ——The light __________for 2 hours.6. He left here 2 years ago.———He ____________from here for 2 years.7. The film began 30 minutes ago. ——The film __________ for 30 minutes.8. They opened the door an hour ago. ——The door __________ for an hour.9. They closed the door an hour ago. ——The door ___________for an hour.10. He joined the army last year. ——He _________ a ____ for a year.He _____________ the army for a year.It ____ a year ____ he joined the army.一、单项选择。

1、Both his parents look sad. Maybe they ______what's happened to him.A. knewB. have knownC. must knowD. will know2、He has ___ been to Shanghai, has he ?Ａ. already Ｂ.never Ｃ.ever Ｄ. still3、Have you met Mr. Li ____？Ａ. Just Ｂ. ago Ｃ.before Ｄ.a moment ago4、The famous writer _____ one new book in the past two year .Ａ. is writing Ｂ.was writing Ｃ.wrote Ｄ.has written 5、—Our country ____ a lot so far .—Yes. I hope it will be even ______ .Ａ. has changed ; well Ｂ. changed ; good Ｃ. has changed ; better Ｄ. changed; better6、Zhao Lan ______already ______in this school for two years .Ａ. was ; studying Ｂ. will ; study Ｃ. has ; studied Ｄ. are; studying7、We ______ Xiao Li since she was a little girl .Ａ. know Ｂ. had known Ｃ. have known Ｄ. knew8、Harry Potter is a very nice film. I _____ twice.Ａ. will see Ｂ. have seen Ｃ. saw Ｄ.see 9、—These farmers have been to the United States .—Really? When _____ there ?Ａ. will they go Ｂ.did they go Ｃ. do they go Ｄ. have they gone10、—______ you ___ your homework yet ?—Yes. I _____ it a momentago.Ａ.Did; do; finished Ｂ.Have; done; finishedＣ.Have; done; have finishedＤ. will; do; finish11、His father ______ the Party since 1978 .Ａ.joined Ｂ. has joined Ｃ. was in Ｄ. has been in 12、—Do you know him well ?—Sure .We ______ friends since ten years ago .Ａ. were Ｂ. have been Ｃ. have become Ｄ. have made13、—How long have you ____ here ?—About two months .Ａ. been Ｂ. gone Ｃ. come Ｄ. arrived14、Hurry up! The play __________ for ten minutes .Ａ. has begun Ｂ. had begun Ｃ. has been on Ｄ. began 15、It ___ ten years since he left the army .Ａ. Is Ｂ. has Ｃ. will Ｄ. was16、Miss Green isn't in the office. She_______ to the library.Ａ.has gone Ｂ. went Ｃ.will go Ｄ. has been17、My parents ______ Shandong for ten years.Ａ. have been in Ｂ. have been toＣ. have gone toＤ. have been18、The students have cleaned the classroom, ____?A. so theyB. don’t theyC. have theyD. haven’t they19、has Mr. White been a member of Greener China since he to China?A. How soon, comesB. How often, gotC. How long, cameD. How far, arrived20、His uncle for more than 9 years.A. has come hereB. has started to workC. has lived thereD. has left the university二、句型转换。