1、时态小结复习（七）：现在完成时【现在完成时】 基本用法：.“已完成”用法:表示一个过去发生并结束的动作对现在造成的影响或结果。这一类情况可以细致分为下述两种情况。1）表示开始于过去的动作刚刚结束。常和 just，now，already，yet ，notyet 等不确定的时间状语连用。Li Ming has just turned off the light. 李明刚刚把灯关上。 （说明现在灯关上了） 2）表示过去动作的结果，现在仍残留着。 。 I have lost my pen. 我把笔丢了。 （说明过去某时丢的，现在我还没找到这支笔）.“未完成”用法。表示动作或状态从过去某时开始，持续到现
2、在，可能继续下去，也可能刚刚结束。常和表示一段时间的状语连用。如 today，this week（month） ，lately，recently ，these days，in the past few days，during the last two weeks，since，since yesterday，since 2 days ago，since 1991，for a long time，for a month，so far，up to now，till（until） nowTheyve known each other since childhood. 他们从小彼此相识。 （现在还在往来
3、）.经验性用法:表示从过去开始到目前为止这段时间中反复发生的动作或多次出现的状态。常与频度副词如 often, always, every week, twice 等连用。I have been to the Summer Palace twice. 我曾经去过颐和园两次。 He has always said so.他总是这么说.构成： 现在完成时的构成：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可以用来表示发生在过去某一时刻的,持续到现在的动作（用行为动词表示）或状态（be 动词表示）常与 for（+时间段）,since（+时间点或过去时的句子）连用. 时间状语：for+时段；si
4、nce+过去一个时间点（自从以来）；since+时段+ago；since+从句（过去时）；It is+ 时段+since+从句（过去时）以 so far（到目前为止）+before 、ever 、never、already, just、yet 为标志肯定句式： 主语 + have / has been + done.Ive finished my homework now. 现在我已经做完作业了。 否定句式： 主语 + have/has + not + done + 其它.He hasnt lived here for 30 years. 他已经不住在这儿三十年了。 一般疑问句： Have/H
5、as + 主语 + done + 其它？ 肯定答语 Yes，主语 have/has. 否定答语 No，主语 havent/hasnt.Have you studied English for three years? 你们学了英语三年吗？ 特殊疑问句： 特殊疑问词 + have/has + 主语 + done + 其它？How long have you studied English？ 你学英语多久了？ 现在完成时的时间状语 I 现在完成时属于现在时范围，故不能和过去的时间状语连用。如：yesterday, last Sunday, in1990, three years ago 等。但是，
6、在强调动作产生的后果和影响时，可以和一些表示不确定的时间状语连用。时态小结复习（七）：现在完成时a. 用副词 already 和 yet。already 一般用于肯定句中，yet 一般用于否定句和疑问句中。b. 用 ever 和 never.多用于否定或疑问句中，表示“曾经”或“从未”等。 c. 用表示到说话为止的过去时间状语，如 just, before, up to now, the past few years 等。d. 用包括“现在”在内的时间状语，如 now,today,this morning(month,year,term)等。 II 短暂性动词不能和表一段时间的时间状语连用。如
7、：come, go, arrive, reach, hear, close, leave, begin, start, lose, buy, fall, join, die, get up 等。但如果要保留表一段时间的时间状语，必须将动词改为延续性动词。现归纳总结一下由非延续性动词到延续性动词的转换begin/start be on go there be thereleave be away get home be homedie be dead open be openjoin be in / be a member of close be closedfall asleep (ill)
8、be asleep (ill) get to know knowget married be married borrow keepcome here be here buy havecatch (a cold) have (a cold) put on wear 或 be ongo to school be a student finish( end ) be over规律总结:1.直接用延续性动词 buy have；catch(get) a coldhave a cold；borrowkeep；become be；put on- wear 2.转换成 be+名词 join the army
9、 be a soldier；join the Party be a Party member； go to school be a student 3 转换成 be+形容词或副词 diebe dead； come to/ go to/arrive at(in)+某地be in(at) +某地4.转换成 be+介词短语 go to school be in school ； get up - be up；例： I bought the pen three days ago. = I have had the pen for three days.The train left five minut
10、es ago. = The train has been away for five minutes.I borrowed a book from the library a week ago. = I have kept a book for a week.不可延续性动词现在完成时的否定式，已变成一种可以延续的状态，因此可以和表示一段时间的状语连用。如： I havent left here since 1997.自从 1997 年以来，我一直没有离开过这儿。 （错）I have received his letter for a month. （对）I havent received hi
11、s letter for almost a month. ( ) 1.Have you met Mr. Li _?A. just B. ago C. before D. a moment ago( ) 2.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 ; better( ) 3.We _ Xiao Li since she was a little girl.A. know B
12、. had known C. have known D. knew( ) 4.Harry Potter is a very nice film .I_ it twice.A. will see B. have seen C. saw D. see( ) 5._ you _ your homework yet? Yes. I _ it a moment ago.A. Did; do; finished B. Have; done; finished C. Have; done; have finished D. will ; do ; finish( ) 6.Miss Green isnt in
13、 the office. She_ to the library.A. has gone B. went C. will go D. has been1.They have been here since 2000. (对划线部分提问) have they been here?2.The old man _ last year. He for a year. (die)（动词填空）3.Miss Gao left an hour ago. (同义句转换) Miss Gao _ _ _ _ an hour ago.4.Her mother has been a Party member for three years .（同义句） Her mother _the Party three years _ .
