1、现在完成时n 1.构成n have/has+过去分词（done）通常使用现在完成时的几种情况n（1）表示过去发生的某一动作对现在造成的结果或影响。n The disappearence of Justin has made Kelly very unhappy.n（2）表示动作从过去开始，持续到现在。n Justin has lived in Dover since he was born.n（3）表示动作的确切时间不明确或不重要n The boy has already come home.n(4)表示刚结束的动作n The police have just finished searchi
2、ng Justins home.n(5)表示反复发生的动作n Some villagers say that they have seen UFOs many times.常与现在完成时连用的时间状语n(1).情况(1)(3)(4)nalready,yet,ever,just,recently,lately,never,before(adv.)n The boy has already/just got home.n I havent heard from him yet/recently/lately.n I have seen the old man somewhere before.(2
3、).情况(2)since/forn I have lived in Beijing since 2000.since I arrived here.for 5 years.(3).情况(5)times,recently,latelyn Some villagers say that they have seen UFOs many times/recently/lately.现在完成进行时n 1.构成n have/has+been+现在分词（doing）通常使用现在完成进行时的几种情况n(1)表示过去开始的动作一直延续到现在并仍在继续之中n She has been talking to me
4、 since she saw me.n(2)表示过去开始的动作刚结束并在某种情况下与现在有关联n Sorry I am late.Have you been waiting long?n Yes.I have been waiting for an hour.现在完成时与现在完成进行时的区别n 1.现在完成时与现在完成进行时都表示动作从过去开始，但现在完成时表示事件或动作刚结束，而现在完成进行时则强调动作仍在继续n I have read a book.n I have been reading a book.n 2.现在完成时可表示反复发生的动作，提问时用how many times。而现在
5、完成进行时则表示持续的、不间断的动作，提问时用how longn I have visited Egypt twice this month.n How many times have you visited Egypt?n I have been visiting Egypt for two months.n How long have you visited Egypt?n 3.现在完成时可以用持续性动词和短暂性动词作谓语，而现在完成进行时则只能用持续性动词。I have done my homework.I have finished my homework.I have been doing my homework.I have been finishing my homework简而言之：n 短暂性动词n 不可以用于现在完成进行时，n 只能用于现在完成时n 4.现在完成时的句子中可以用像never、yet、already和ever等作时间状语，而现在完成进行时的句子中则不可以用这样的词n I have already been to Beijing.n I have never been to Beijing.n I havent been to Beijing yet.
