现在完成时时态讲解.docVIP

时态讲解：现在完成时 （1）构成：现在完成时由助动词have + 过去分词构成，助动词have 有人称和数的变化。第三人称单数用has，其余用have. 现在完成时的否定式直接在助动词后面加上not、疑问式是把助动词提到主语之前。以study 为例，其否定式、疑问式和简单回答形式如下：否定式 疑问式 I have not (haven’t) studied…. Have I studied…? You have not (haven’t) studied…. Have you studied…? He has not (hasn’t) studied…. Has he studied…? 否定疑问式 简单回答（肯定/否定） Have I not (Haven’t I) studied…? Yes, you have. No, you haven’t. Have you not (Haven’t you) studied…? Yes, I have. No, I haven’t. Has he not (Hasn’t he) studied…? Yes, he has. No, he hasn’t. （2）用法： 1）现在完成时通常表示在说话之前已经完成的动作或存在的状态。说话人强调的是该动作或状态对现在的结果或影响。 My daughter has just gone out. 我女儿刚出去。 I’m sure we’ve met before. 我肯定我们以前见过面。 She has arrived. 她到了。 2）表示持续到现在的动作或状态，往往和包括现在在内的表示一段时间的状语连用，如recently, lately, for…, since…,yet等。如： I haven’t heard from her these days. 这些日子我没有收到她的信。 We haven’t seen you recently. 最近我们没有见到你。 They have been away for two years. 他们离开已经两年了。 She has been with us since Monday. ★注意： since和for的区别 since后接时间点，如1993，last term, yesterday, the time I got therefor后接一段时间，表示“长达多久”，如ten years, a while, two days等。 Ex: 用since和for填空 1. Jim has been in Ireland ______ Monday.2. Jill has been in Ireland ______ three days. 3. His aunt has lived in Australia ______15 days. 4. Mary is in her office. She has been there ______ 7 oclock. 5. India has been an independent country ______1974. 6. The bus is late. Theyve been waiting ______ 20 minutes. 7. Nobody lives in those houses. They have been empty ______ many years. 8. Mike has been ill ______a long time. He has been in hospital ______ October. 1. since 2. for 3. for 4. since 5. since 6. for 7. for 8. since 2）表示短暂意义的动词如arrive, leave, borrow, buy, begin, start, die等，在完成时当中不能和表示一段时间的状语连用，因为它们表示的动作不可能持续。因此，不能说： He has come here for 2 weeks. × The old man has died for 4 months. × They have left only for 5 minutes. × 以上三句话可以改为： He has been here for 2 weeks. The old man has ______ _______ for 4 months. They have _____ _____ only for 5 minutes. 3）hav