1、1现在完成时的讲解对所学时态的回顾，引入现在完成时通过数轴来概括讲解所学的四个时态：一般现在时、现在进行时、一般过去时、一般将来时。（导入）有时候，这 4 种时态还不能满足我们表达的需要。比如：表示“某人过去曾经做过某事”或者“某人做某事多久”，以上五种时态就派不上用场了。这时，我们可以用一种新的时态现在完成时表示。同样也用数轴来表示一下。一 现在完成时的构成:主语 + have/has + 过去分词(过去分词 :规则动词的过去分词构成与动词过去式相同;不规则动词需要特殊记忆。 eg .I have taught English in this school since 1999.二、否定式:
2、主语 + havent/hasnt + 过去分词。疑问式: Have /Has + 主语 + 过去分词?简略答语: Yes, 主语 + have/has.(肯定) No, 主语 + havent/hasnt.(否定)Have you finished your work? Yes,I have. 三 现在完成时的含义之一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，常与 already/yet，just，never/ever，before, so far 等连用。这些标志词可以表达这种含义.1already 意为“已经”，通常用于肯定句中，可放在助动词之后，过去分词之前，也可以放在句末。
3、实例：1）Ive already read this book. 我已经读过这本书了。（“读”这一动作发生在过去，对现在造成的影响是“知道书中的内容”。）2）Ive washed my clothes already 我已经洗了衣服。（洗衣服的动作已完成，其结果是“衣服冼干净了”。）2注意：在表示吃惊或明知故问等感情色彩时，already 也可用于（口语）疑问句中。实例：3）Have you met him already ？你（真的）已经见过他了？2yet 用在疑问句中意为 “已经”，用在否定句中意为 “还”，常放在句末。实例：1）Has he found his watch yet ？他已
4、经找到他的手表了吗？No，not yet不，还没有。2）The woman hasnt found her dog yet 那位妇女还没有找到她的狗。（没找到狗，心里着急，这就是对现在的影响）3just 意为“刚刚”，表示行为刚刚过去，常放在助动词与过去分词之间。实例：He has just come back from school 他刚从学校回来。4ever 意为 “曾经”，用于疑问句或否定句中，放在助动词与过去分词之间。实例：1）Have you ever been to Hong Kong ？你曾去过香港吗？2）I havent ever spoken to her我未曾和她说过话。5
5、never 意为“从来没有 ”常与 before 连用（before 要放在句尾，而 never 多放在助动词与过去分词之间。实例：I have never traveled by plane before我以前从来没有乘飞机旅行过。6before 意为 “以前”，指过去不确定的某个时间，总是放在句末，不受句型的限制。实例：1）Have you been to Hainan before ？你以前去过海南吗？2）I havent eaten Guangdong food before我以前没吃过广东菜。7. 以 so far 为标志so far 往往表示到目前为止动作或状态已经发生。He ha
6、s got to Beijing so far. She has passed the exam so far.四、现在完成时含义之二表示过去已经开始,一直延续到现在的动作或状态。常与 for, since, how long, these days 等连用。since+过去时间点since+过去时的从句since+一段时间+ago（since 短语或从句表示过去的动作延续至今，since 之后的时间为一点）Mr. Smith has worked here since 1984. Hes learned about 5,000 English words since he went to c
7、ollege. My uncle has worked at this factory since five years ago.for+一段时间（数词+量词），（for 短语表示动作延续多长时间，for 的宾语为时间段）。3此划线部分用 how long 提问。We have known each other for twenty years. I havent seen her for a long time.五、句式：It is/has been 一段时间since 从句（用一般过去时）It is /has been ten years since she left. 六、have be
8、en in, have been to 与 have gone to 的用法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。例如：Mr. Brown has been in Shanghai for three days. 此外还有这些搭配：have been here (there) /at home (school) /on the farmhave been here (there) / abroadhave(has)been to 表示“曾经去过某地”，现在已经不在那里了。可与 just, e
9、ver, never 等连用， I have just been to the post office. Mary has never been to the Great Wall. Have you ever been to Hangzhou? have(has) been to 后面可接次数，表示去过某地几次。：I have been to Beijing three times.。They have been to that village several times. have(has) gone to 意为“到某地去了”，表示到了某地或正在去某地的途中。总之，说话时该人不在现场，一般
10、不用第一、第二人称代词作句子的主语。-Where is Tom? -He has gone to the bookshop.。七、现在完成时的反意疑问句【have（nt）/has（nt）代词】( )1.Jims been to the Great wall before , he?(A)isnt (B)wasnt (C)hasnt (D)doesnt( )2.Shes never been to England, she?(A)has (B)hasnt (C)isnt (D)is八、How long 与现在完成时( )1.-_have you been here? - Since last y
11、ear(A)How far (B)How long (C)How often (D)How soon( )2._has Hanmei been in the library.(A)How long (B)How soon (C)How far (D)How often( )3.How long _he_the library book .(A)has, borrow (B)has, kept (C)has, bought (D)did, buy九、延续性动词与非延续性动词动词按其动作发生的方式、发生过程的长短可分为延续性动词与非延续性动词。1.延续性动词表示能够延续的动作 ,4如：learn,
12、 work, stand, lie, know, walk, keep, have, wait, watch, sing, read, sleep, live, stay 等。延续性动词可以与表示时间段的状语连用。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+时间点词,since last year, since 5 days ago; how long; for a long time 等。2.非延续性动词也称终止性动词、瞬间动词 ,表示不能延续的动作,这种动作发生后立即结束。如:open, die, c
13、lose, begin, finish, come, go, move, borrow, lend, buy 等。 非延续性动词在肯定句中与表示时间点的状语连用，如：two years ago; at 5 oclock; 否定的终止性动词可以与表示时间段的时间状语连用。非延续性动词转化成延续性动词1、转化为相应的延续动词borrowkeep buyhave catch a coldhave a cold put on wearget to knowknow get to sleepsleep2、转化为“ be+形容词/副词/ 介词/名词”go/comebe +相应的介词短语 come back
14、be back begin/startbe ongo outbe out get to/arrive/reachbe(in) leavebe away（be not here） diebe dead openbe open leavebe leave finishbe over fall illbe ill closebe closed losebe lost turn onbe on get upbe up becomebe go to schoolbe in school sit downsit/be seated joinbe in（ ）或 be amember go to bed be
15、 in bed make friendsbe friends 例：1）他入团两年了。误：He has joined the League for two years正：He has been a League member for two years2）我买这辆自行车三年了。误：I have bought this bike for three years正：I have had this bike for three years5十、现在完成时与一般过去时的用法比较现在完成时表示过去的动作一直延续到现在甚至会继续下去或表示过去的动作对现在造成的影响；一般过去时表示动作发生的时间在过去。试比较
16、：The plane has arrived . 飞机已经来了。（说明现在的情况：飞机在这儿）The plane arrived a quarter ago. 飞机是一刻中以前来的。（强调动作发生的时间在过去）I have taught here for fifteen years. 我在这儿已经教了十五年。（表示十五年前的动作一直延续到现在，还可能会继续。）I taught here for a year. 我过去在这儿教过一年。（表示“我”现在已经不在这儿任教了）When 常与一般过去时连用，How long 常与与现在完成时连用When did you come to Beijing?How long have you been in Beijing?
