二十一、高考时态现在完成时
现在完成时一个动作开始于过去,持续到现在。表示从过去延续到现在并包括现在在内的一段时间的状语有:lately, recently, in the last/past few days/years(在过去的这几天/年里),since then, up to now, so far(至今)等。In the past few years, great changes have taken place in my hometown.一个发生在过去的事情对现在产生的影响。常用的状语有already, just(刚刚),yet(已经),never, before 等。Already 用在肯定句中,yet 用在否定句和疑问句中; already用在句中,yet 用在句末。I have already seen the film. (=I know the film now.)I havent seen the film yet.Have they arrived yet?This/It/That is the +序数词/only/best/most +time +(that)+ sb. have/has done, “这是某人第几次做某事”。This is the first time that I have come here.现在完成时用在条件、时间、让步状语从句中,表示将来完成时。I will not believe you unless I have seen it with my own eyes.It is/has been +一段时间+since 从句,since 从句用一般过去时,“自从 以来已经有多久了”。It is/has been 10 years since we met last.瞬间动词又叫非延续性动词、终止性动词。瞬间动词一般不用完成时态,也不可以接表示一段时间的状语,若要接,需要做一些相应的变换。瞬间动词的否定可用完成时,也可接表示一段时间的状语。× He has come to Beijing since last year. He has lived in Beijing since last year.× He has joined the army for 3 years. He has served in the army for 3 years. He joined the army 3 years ago. He has been a soldier for 3 years. It is 3 years since he joined the army. 常见的瞬间动词有:come, go, get to/reach/arrive at, leave, buy, sell, open, close, get up, join/take part in, begin/start, return/give, borrow/lend, become/turn, bring/take, die, finish/end, receive/hear from, marry, break, lose, jump 等。现在完成进行时现在完成进行时主要用于:表示过去开始的某一动作一直持续到现在,以至延伸到将来,它强调动作延续时间之长久。e.g. I've been writing an article. 我一直在写一篇文章。 (还在写) cf. I've written an article. 我写了一篇文章。 (已写完) It has been raining these days. 这些天一直在下雨。 在不用时间状语的情况下,现在完成进行时表示动作仍在进行。而现在完成时则表示动作在过去已结束。如:The students have been preparing for the exam.(还在进行)学生们一直在准备考试。The students have prepared for the exam.(已经结束)学生们为考试作了准备。