现在完成时专题.pptVIP

现在完成时谓语动词的构成： 1. I _____________(finish) homework already. 句式变换： 1. He has finished his homework.(变为否定句） 2. They have visited China before.(变为一般疑问句，并做肯定回答） 想一想 1.现在完成时的第一种用法是什么？ 2.常用的时间状语有哪些？ 3.你能说出already 和yet 有哪些不同吗？ 现在完成时(一) 1.表示过去发生的动作对现在造成的影响和结果. 2.时间状语: already, yet, ever,never,just,before等 3.already 和 yet 的区别 already 多用于肯定句；yet多用于否定句和疑问句末。 1.I ________ (do) my homework already. 2.He _____________(not finish) his homework yet. 3.We ______ never ______ (see) this book before. 5.Mother _____ just _______(clean) the house. 6.Sally __________(visit) China before. 现在完成时(二) 1.现在完成时的第二种用法是什么？ 2.常用的时间状语有哪些？ 3.你能说出for 和since有什么不 同吗？ 你能说出一般过去时和现在完成时的区别吗？ 一般过去时与现在完成时有一些明显的时间状语。 1.yesterday, last year, in+过去某一年，two days ago, just now等常用于一般过去时 2. already, yet, ever, never, just, before, so far, in the past/ last few years(在过去/最近的几年里)，for+一段时间，since+时间起点等常用现在完成时 Homework * * Our slogan: He who has never been to the Great Wall isn’t a true man. 现在完成时 Revision The Present Perfect Tense 2. He ___________(learn) English for three years. I/ We/You/ They have … He/She/It has … have finished has learned 助动词have/has +pp（过去分词） He hasn’t finished his homework. Have they visited China before? Yes, they have. 注意：如果肯定句中含有already或just ，在变成否定句或疑问句时，要把句中的already 或just 转换成yet. I haven’t seen the film yet. 2.I have already finished my homework. Have you finished your homework yet? 3. Mother has just cleaned the house. Mother hasn’t cleaned the house yet. 1. I have already seen the film. have done has not finished have seen has cleaned has visited 用动词的适当形式填空： 现在完成时(二) 1.表示过去发生的动作,一直延续到现在, 并且有可能继续延续下去. 2.时间状语: 通常和for, since 引导的时间状语连用. 1.for + 一段时间 for a week, for 3 years, for a long time, 2. since +时间起点 since+一段时间+ago since+从句(一般过去时) since 2 o’clock, since yesterday, since3 years ago, since I came here等 . 注意: 对for或since