Unit 3 Food and Culture Learning about language 语法课件-2023-2024学年高中英语人教版（2019）选择性必修第二册

现在完成时与过去完成时的区别 The present perfect tense & The past perfect tense I have waited here for an hour. She has waited here for an hour. 现在完成时的构成： have/has(not)+done 现在完成时的概念： 1.表示过去发生的动作对现在造成影响； I have seen the film many times，so I won’t go with you. 2.表示过去某一时间开始一直延续到现在的动作。 He has lived here since 1949. 现在完成时的用法： 1.现在完成时强调过去动作与现在的联系,也就是强调现在的影响和结果，故常与表示包括现在在内的时间副词，如recently, just,already,before,yet,never,ever等状语连用 eg. I have never heard of that before. She has already known the news 2.常与for或since引导的时间连用，这时动词需使用延续性动词 for+一段时间 eg. He has lived here for 5 years. since+ （表示过去某一时间的）时间点 eg. He has been here since 5 years ago. 其他标志语： 如：so far,up to now, by now,since then, these days, in the last/past few days/years 现在完成时的用法： 3.句型 This/ It is the first/ second/ ...time (that)...也常与现在完成时连用 现在完成时的用法： This is the third time that he has driven a car. 过去完成时 7 构成：助动词had + 动词的过去分词（V.pp) 用法： 1. 过去完成时动词表示过去某一时间或某一动作之前完成的动作或状态。强调过去某一动作发生在另一动作之前时。 过去完成时： 在强调过去某一个动作发生在另一个动作前常常用过去完成时态。 1.他说他以前见过你。 He said that he ______________ (see) you before. had seen 2. 到六点钟为止他们已经工作八小时了。 By six o’clock they ______________(work) for eight hours. had worked 过去分词的构成： 1. 规则动词的变化： a) 一般情况下在动词后面加 ed work ------ worked play -------- played b) 以 e 结尾的动词直接加 d use ------ used refuse ------ refused c) 以辅音字母加 y 结尾的动词，把 y 改 i 再加 ed study ----- studied carry ----- carried d) 以重读闭音节结尾的，前面有单个元音字母时，双写辅音字母，再加 ed stop ---- stopped drop ------- dropped 2. 不规则动词的变化见不规则动词表 过去完成时的构成：由助动词had + 动词的过去分词（V.pp) 2. 过去完成时词可以表示过去某一时刻之前发生的动作或呈现的状态，这一动作一直持续 或将继续下去。 By six o’clock they ____________ (work)for eight hours. When I came to GZ , he _____________(be) there for a long time. 用法： 1. 到了六点钟为止，他们已经工作了八小时了。 2. 我到广州时，他在那里很长时间了。 had worked had been 3.到上个月中旬我们在北京住了有五年时间了。 By the middle of last month we ______________(live) in Beijing for five years. had lived 1. 到昨晚上，他已写完那封信。 By yesterday evening he ___________ (write) that letter. 2. 他说他以前见过你。 He said that he ____________(see) you bef