Unit 7 语法-现在完成时 课件 2025-2026学年人教版英语八年级下册

The present perfect continuous tense 现 在 完 成 时 Unit 7 - Grammar 现在完成时的定义: 现在完成时表示过去发生的动作或状态对现在造成的影响或结果,或者从过去某个时间开始一直持续到现在的动作或状态。 现在完成时的结构: 主语 + have / has + 过去分词 注:主语为单三,则助动词用has 过去分词的变化规则:规则变化 Point 规则动词的过去分词与过去式形式相同。 在动词后加-ed help-helped-helped clean-cleaned-cleaned 以字母e结尾的动词,加-d move-moved-moved die-died-died “辅音字母+y”,变y为i,加-ed study-studied-studied carry-carried-carried 辅元辅结尾的重读闭音节,双写最后一个辅音字母,再加-ed stop-stopped-stopped plan-planned-planned 现在完成时的用法: 1. 影响性用法:动作发生在过去,但对现在造成了影响或结果。 I have already had lunch. (Implies: I am full now.) 2. 表示一个动作到现在已经发生了多少次。 I've already read Around the World in Eighty Days twice. 3.持续性用法: 动作开始于过去,一直持续到现在。 He has lived here for ten years. 现在完成时的基本句型: Point 肯定句:主语 + have/has + 过去分词 + ... 否定句:主语 + haven’t /hasn’t + 过去分词 + ... 一般疑问句:Have/Has + 主语 + 过去分词 + ... ? 答语:Yes, 主语 + have/has . / No, 主语 + haven’t /hasn’t. 特殊疑问句:How long + have/has + 主语 + 过去分词? 答语:直接用since/for引导的短语作答 易错点:不可用When提问持续时间,只能用How long —How long have you been here? —For three months. 1 2 3 —How long have you known your best friend? —I have known my best friend for five years. —How long have you had your favourite toy? —I have had my favourite toy for six months. —How long have you lived in your neighbourhood? —I have lived in this neighbourhood since 2023. 辨析: how long, how often, how soon 和 how many times 疑问词组 中文含义 询问重点 典型答语 How long 多久、多长时间 动作或状态持续的总长度(时间段) for + 时间段 since + 时间点 How often 多经常、频率如何 动作发生的频率(规律性) once/twice a week (每周一/两次) every day(每天) sometimes(有时) How soon 多快、还要多久 将来动作过多久后会发生(时间点距现在的间隔) in + 时间段(eg.in ten minutes) How many times 多少次 到说话时为止,动作发生的总次数(累积数字) once(一次) three times(三次) many times(许多次) - “ will you finish your homework?” - “In an hour.” 2 - “ do you visit your grandparents?” - “Once a month.” 3. - “ have you been waiting?” - “For about twenty minutes.” 4. - “ have you seen this movie?” - “Only once.” How soon How often How long How many times Point 1. already表示“已经”,强调动作的完成,常用于肯定句中。 I've already finished reading the book! 我已经读完这本书了! 注意:already一般置于助动词 have/has之后,过去分词之前。 2. yet常用在否定句中, 表示“尚未, 还未”,用在疑问句中表示“已经”。 ① Silvia has bought a new dress, but she hasn't worn it yet. ② - Have you read the book yet, Harry?  - Yes, I have. 注意:yet一般置于否定句或疑问句的结尾处。 时间状语(一)-副词 Point 3. ever 表示 “曾经”,主要用于肯定句和疑问句。 - Have you ever been to a science museum? - Yes, I have. 4. never 表示 “从来没有,从不”,表示否定,主要用于否定句。 Let's go to the space museum. I've never been there. 注意:never, ever一般置于助动词have/has之后,过去分词之前。 时间状语(一)-副词 时间状语(一)-副词 Point 4. just 强调动作 “刚刚(不久前)完成”, 位于 “have/has” 之后。 I have just finished my homework. 注意:just now 表示 “刚刚”,用作一般过去时态的时间状语。 5. before 表示 “以前”, 用在句末后。 I have never read this kind of books before . 注意:before + 时间,不用在现在完成时态中。 时间状语(一)-副词 Point 6. 现在完成时态常与recently, so far ,in the past / last few years等时间状语连用。 She has passed all the exams so far. 到目前为止她已经通过了所有考试。 7.现在完成时态常与once,twice, three times,several等表示重复次数的词语连用。 He says he has been to the USA three times. 他说他已经去过美国三次了。 1.for+时间段2.since+时间点(过去)3.since+一段时间+ag0=for+时间段4.since+从句(常用一般过去时)5.It's+一段时间+since(过去时的句子) 时间状语(二)- for & since Point for 与 since 的用法 since + 时间点 = 时间段 for + 时间段 for 与 since 表示引出的时间状语,表示:过去已经开始, 一直持续到现在的动作或状态 I have been a volunteer here for a few months. She has been a volunteer at a nursing home since last August. Point 时间状语(二)- for & since 一、用 for 和 since 填空。 three hours a week three o'clock a long time two days 1997 yesterday afternoon for two weeks three years ago I came here last month for for since for for since since for since since since 1.for+时间段2.since+时间点(过去)3.since+一段时间+ag0=for+时间段4.since+从句(常用一般过去时)5.It's+一段时间+since(过去时的句子) 时间状语(二)- for & since Point for 与 since 的用法 since for + 时间段 + 时间点( 过去 ) + 一段时间 + ago = for + 时间段 + 从句( 一般过去时 ) It is / has been + 一段时间 + since 从句(一般过去时 ) They have lived here since they got married. He has taught in this school for eight years. It has been three months since she called last time. It is two years since I graduated. At the meeting, the managers kept arguingabout the problemthey reached an agreement. A.after C.until B.when D. since 1. - How long has she the science book? I want to borrow it from her. - For nearly three weeks. I think she might have finished reading it. A. buy B. had C. bought 2. - Why are you in such a hurry? - Because the class for 10 minutes. A. is on B. begins C. has been on D. has begun 3. Chengdu is a beautiful city and Tom there three times since he came to China. A. is B.was C. will be D.has been B C D At the meeting, the managers kept arguingabout the problemthey reached an agreement. A.after C.until B.when D. since 1. Recently,more and more people have (choose ) to visit Yangzhou during holidays. 2. I have (regret )never choosing to be kind, even when it was not easy. 3. Mr. Zhang is an experienced teacher. He has (teach ) geography for overthirty years. 4. -Do you know Mount Wudangin Shiyan? -Yes, I have (climb) it twice. It's fantastic. 5. I _(be) a member of the Red Cross for six years. I’ve made a lot of friends _ I joined the organization. chosen regretted taught climbed have been since Thanks ! $