【课堂新坐标】（教师用书）2013-2014学年高中英语 Unit 9 Period Ⅲ On the Move Clean Machines课件 北师大版必修3.ppt

观察下列从Reading中选取的句子，体会现在完成时和现在完成进行时的用法。 ①People have been worried about pollution caused by fuels. ②Youve been designing solar racing cars for a long time. ③I have been interested in cars since kindergarten. ④I have designed five or six different cars so far. ⑤I have been taking part in races for about four years. ⑥So far Ive only written the first few chapters. [自我总结]　以上六句话都表示 开始的动作，延续到 的过程。其中①③④⑥句的结构为：have/has＋过去分词，是 ；②⑤句的结构为：have/has＋been＋现在分词，是 。 【答案】　过去；现在；现在完成时；现在完成进行时 现在完成时和现在完成进行时 一、现在完成时的构成 1．现在完成时由“has/have＋动词的过去分词”构成，第三人称单数用has，其他人称用have。 2．现在完成时的肯定、否定、一般疑问式及其回答(以do为例)。 二、现在完成时的概念及其用法 1．某动作开始于过去，持续到现在(也许还将持续下去)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. 在过去的几年里，我的家乡发生了巨大变化。 He has been busy writing a book recently. 最近他一直在忙着写书。 2．过去发生的事情对现在产生的影响，注意这时说话者说话的重心是过去的事情对现在产生的影响。常用的状语有already，just(刚刚)，yet，never，before等。 I have already seen the film.(＝I know the film now.) 我已经看过这部电影。 3．This/That/It is the first/second/...time＋that从句that从句中谓语动词要用现在完成时。 This is the first time(that) I have come here. 这是我第一次来这里。 4．在条件、时间、让步状语从句中，表示将来某时以前已经完成的动作。 I will not believe you unless I have seen it with my own eyes.只有我亲眼看到，我才会相信你的话。(强调“看完”) I will go with you as soon as I have finished my work. 我干完了工作就和你一起去。(强调“干完”) 5．瞬间动词又叫非延续性动词，还叫终止性动词。瞬间动词可以有现在完成时态，但不可以接一段时间，若要接一段时间，需要做一些相应的变换。瞬间动词在完成时态中的否定式可以接一段时间。 (×)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. (√)He has joined the army. 常见的瞬间动词和短语有：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