现在完成时 1.概念：过去发生或已经完成的动作对现在造成的影响或结果，或从过去已经开始，持续到现在的动作或状态。 2.时间状语：yet,already,just,never,ever,so far,by now,since+时间点，for+时间段，recently, lately, in the past few years, etc. 3.基本结构：主语+have/has +p.p（过去分词）+其他 4.否定形式：主语+have/has + not +p.p（过去分词）+其他 5.一般疑问句：have或has。 6.例句：I've written an article.            The countryside has changed a lot in the past few years.

现在完成时

行时。如： I’ve known him for many years. 我认识他有许多年了。 The war has lasted for a long time. 这场战争持续了很长时间。   有少数动词(如live, work, teach, study等)用两种时态都可以，意思差别不大。如： I’ve lived [been living] here for 30 years. 我在这儿住了30年了。 How long have you worked [been working] here? 你在这里工作多久了?   现在完成时与现在完成进行时的相通性：在表达一个从过去开始而现在仍在继续或刚刚结束的动作时， 某些动词既可以用现在完成时，也可以用现在完成进现在完成时强调动作的完成，而现在完成进行时强调动作的延续，因此，表示动作的完成，只能用现在完成时，而不能用现在完成行时，如 expect, hope, learn, lie, live, look, rain, sleep, sit, snow, stand, stay, study, teach, wait, want, work等。 如：你学习英语多久了? 正：How long have yon learnt English? 正：How long have you been learning English? 他已经睡了十个小时了。 正：He has slept for ten hours. 正：He has been sleeping for ten hours.  

弟弟参军两年了. My brother joined the army two years ago. ⑵.若保留for+时间段,since+时间点/从句, 或用在 how long 句型中,则需将终止性动词改为相应的状态动词或延续性动词 常见瞬间动词与延续性动词(或状态动词)的对应关系: come/go/arrive/get/reach/move------be in/at open-----be open die------be dead close----be closed              become---be borrow---keep begin/start-----be on     put on----wear leave-----be away (from)           fall asleep----be asleep end/finish-----be over     catch a cold-----have a cold join the army----be in the army be a soldier join the Party----be in the Party be a Party member 例： They borrowed the book two weeks ago．他们两个星期前借的这现在完成时表示过去发生的动作对现在造成影响，也表示过去的状态持续到现在本书。 → They have kept the book for two weeks． A month has passed since he left home. 他离开家已经一个月了。 → He has been away from home for a month.  注意：以下表示法的含义及用法 have been (to): 去过或到过（某地）（表示某人过去的经历） have gone (to)：去（某地）了 （现在可能已在某地） have come (to)：来（某地）了 （现在可能已在某地） have been in„ +一段时间: 已在某地一段时间了  例： He has been to Hangzhou several times. 他到过杭州几次了。 He has gong to Hangzhou, so he can’t help us. 他去杭州了，所以他不可能帮助我们。 He has come to our city. Let’s go to visit him. 他已经到我们城市来了，我们去拜访他吧。 She has been in London for half a year. 她在伦敦已经半年了。

行时has been writing谈论的是某事已经发生了多长时间，而现在完成时has written强调的是某事已经完现在完成时态谈论那些过去和现在成了多少。[/cn][en]4 Look at these two sentences.[/en][cn]4 看下面两个句子：[/cn]• I’ve worked here for thirty years. • I usually work in London but I’ve been working in Birmingham for the last 3 weeks. [en]We can use the present perfect simple to talk about how long when we view something as permanent. But the present perfect continuous is often used to show that something is temporary.[/en][cn]我们用现在完成时谈论某件长久的事情。而我们用现在完成进行时表示某件暂时的事。[/cn]

11.11 用于现在完成时的句型   1）It is the first / second time…. that…结构中的从句部分，用现在完成时。 　 It is the first time that I have visited the city. 　 It was the third time that the boy had been late. 2）This is the… that…结构，that 从句要用现在完成时. 　 This is the best film that I've (ever) seen. 　　　 这是我看过的最好的电影

行时关注动作本身，特别是解释动作可见的结果时。 He’s run three miles. (the result: He’s covered the distance of three miles.) He’s been running for an hour. (the activity and its consequences: this is what he’s been doing for the last hour and why he is exhausted now.) 3、现在完成进行时表示重复的动作时，不能同表示具体数字的词并用。 I’ve posted a dozen postcards, but received none. I’ve read this book several times. I’ve been posting postcards since early December. 4、现在完成进行时带有较为强烈的感情色彩。 You have been disturbing me. 5、许多状态动词不能用完成进现在完成时 1、表示过去开始并持续到现在的动作。（动词必须是持续动词） China has changed a great deal in the past 20 years.  2、强调过去动作对现在行时。 I’ve known that for a long time.  The strike has lasted six months. 6、有少数动词用两种时态都可以，但若强调时间长度时用完成进行时较好。 They have been working this term. They have worked very well this term.

一、基本结构：主语+have/has+动词的过去分词　 ①肯定句：主语+have/has+动词的过去分词+宾语. 　　 ②否定句：主语+have/has+not+动词的过去分词）+宾语. 　 ③一般疑问句：Have/Has+主语+动词的过去分词+宾语. 　　 ④特殊疑问句：特殊疑问词或词组+一般疑问句（have/has+主语+过去分词（V-ed）+其他） 过去分词变化规则如下： 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--dropped 2 、 不规则动词变化需参看不规则动词表逐一熟记。例如： cut- cut- cut, hit--  hit-- hit 二、用法　 1 、现在完成时用来表示过去发生或已经完成的动