Unit 8 Lesson 4 Grammar Focus (4a-4d)（讲解课件）-【优翼·学练优】2025-2026学年八年级英语下册同步备课（人教版）

该初中英语课件聚焦现在完成时中for/since的用法及延续性动词转换，通过志愿者服务时长等例句对比，引导学生观察总结for接时间段、since接时间点的规律，衔接基础语法，搭建从具体例句到抽象规则的学习支架，辅以视频加深理解。 其亮点在于以“观察-讨论-应用”逻辑培养思维品质，通过非延续性动词转换表（如join→be a member of）提升语言能力，小组访谈活动（如询问好友认识时长）发展学习能力。实例贴近生活，助力学生掌握语法应用，为教师提供系统教学资源与互动设计。

Unit 8 Making a Difference Section A What can we do to help? Grammar Focus (4a-4d) Learning Objectives In this lesson you will: 1. review the basic structure and usage of the present perfect tense. 2. master the differences between for and since in present perfect tense. 3. understand the use of durative verbs with for/since, and learn to convert non-durative verbs to durative ones. Read the sentences. How are for and since used differently? Have you been to our animal shelter before? No, I haven't. But one of my friends has volunteered here for a long time. Has she ever done volunteer work? Yes, she has. She has been a volunteer at a nursing home since last August. How long have you been a volunteer? I have been a volunteer here for a few months. How long has he worked as a volunteer at the museum? He has volunteered here since his summer holidays started. 4a Think and Discuss What comes after for? What do the expressions have in common? What comes after since? What do the expressions have in common?   “A long time, a few months...” These expressions all refer to a period of time, showing how long an action lasts. “Last August, his summer holidays started...” These expressions all refer to a specific point in the past (either a time phrase or a clause in simple past tense), showing when an action began. What are their differences in meanings？ "For" is used to talk about the length of time an action lasts and we can translate it “持续……”. "Since" is used to indicate the starting point of an action in the past and we can translate it “自从……”. Do the verbs in the sentences with for/since show short or long actions? Why do we use present perfect tense with for/since here? They show long actions that continue from the past to the present. Because the present perfect tense is used to describe an action that started in the past and continues to the present, and "for" and "since" are used to express the duration or starting point of such actions. Watch the video to help you have a better understanding of the differences. Grammar Rules 现在完成时还可以表示从过去某一时间开始，一直持续到现在的动作或状态，常与for/since或how long连用。此时，谓语动词必须为延续性动词。 e.g. They have worked in this company for 30 years. He has been in the army since 2016. How long have you been friends? for & since用法 for后接时间段，表示动作从过去持续到现在的“时长”。 例如：for 3 days、for 2 hours、for 5 years、for a long time、for a while、for several weeks等。 e.g. We have waited for two hours. He has owned this car for a decade. since后接时间点，表示动作“从过去某一时间点开始”并持续到现在。 例如：since 2015(自2015年起)、since 9 o'clock (自9点起)、since he came here(自从他来这儿起)、since last summer(自从去年夏天起)、since childhood(自童年起)、since then(从那以后) e.g. They have worked in this company since two years ago. I have known her since we were in primary school. It has rained since this morning. 1.I have had the toy _______3 years but now I have to part with it because it's broken. 2.He treats the robot as his favorite because he's owned it _______ his fourth birthday. 3.I haven't played football _______ a while because of my backache. 4.I've known Alice_______ five years.I'm sure she won't lie to anyone. 5.Linda has been ill_______ a week ago. Let's bring our notes to her. Complete the sentences with since or for. for since for for since 延续性动词 & 非延续性动词 延续性动词表示可以持续一段时间的动作或状态，动作本身有延续性。在现在完成时中，与for 或since连用的动词必须为延续性动词。常见的延续性动词有 have，live，teach，learn，work，study ，know 等。 e.g. She has lived in London for 5 years. They have studied English since 2020. I have had this book for a month. 非延续性动词表示瞬间发生并立即结束的动作，动作无法持续，不能与表示时间段的状语(for/since)直接搭配使用。常见词汇 come，go，leave，start，die，finish，become，join，buy，get married 等。要表达延续性状态，要将非延续性动词转换为延续性动词。 e.g. 他入团两年了。 ( × ) He has joined the League for two years. ( √ ) He has been a League member for two years. 这块手表我买了两年了。 ( × ) I have bought this watch for two years. ( √ ) I have had this watch for two years. 非延续性动词可以转换为延续性动词。 非延续性动词 对应的延续性表达 例句 begin/start have/has been on The film has been on for 20 minutes. finish/stop have/has been over The parade has been over for 2 hours. come/go/arrive have/has been in/at Kitty has been in HK for two days. leave have/has been away She has been away from home since Tuseday. borrow have/has kept She has kept this book since last book. join have/has been in have/has been a member of Simon has been a member of the Football Club since last year. marry have/has been married They have been married for 15 years. die have/has been dead The fish has been dead for some time. e.g. I haven't bought any food since last week. The fridge is empty now. Where has Tom gone? We haven't seen him the whole morning. 非延续性动词一般不能与表示持续性时间的状语连用，但在否定结构中，可用非延续性动词的现在完成时表示持续的动作或状态。 Complete the sentences with the correct forms of the verbs in brackets and for or since. 4b 1. This college student enjoys volunteering for the army. She_____ ________(teach) English to the soldiers_____three years. 2. I__________(be) a member of the Red Cross for six years. I have made a lot of friends __________I joined the organization. 3. Mr Wu has taught in a primary school as a volunteer ________ two years now. __________he started working there, he __________(help) many students. 4. The organization___________(train) over 6,000 volunteers __________it began to offer classes three years ago. has for have been since for Since has helped has trained since taught Complete the passage with the correct forms of the verbs in brackets. I love being a volunteer! I____________(work) with a sports organization for almost three years now. Since I started, I ____________ (help) out at over ten different sports events. I ____________(make) many new friends and I ___________ even _________ (meet) many famous athletes. For example, I _____________(meet) two national football players from Argentina last month. They were at a stadium for a charity have worked have helped have made have met met 4c match. The stadium _______(be) so big that they_______ (get) lost. I gave them directions and they________(smile) and____________(thank) me warmly.I am proud to be a volunteer. was got smiled thanked Work in groups. Interview your groupmates using the questions below. Share the answers with the class. How long have you know your best friend/...？ had your favourite toy/...? lived in your neighborhood/...? 4d Sample In our group, Maria has lived in this neighborhood for only one year, but she knows it very well. Tom has lived in the neighborhood since he was a baby. And he has had his favorite toy, a soft teddy bear for 9 years. He received it on his fifth birthday. Tom has a good friend called Jimmy and they have been good friends for six years.... Try to use different tenses we have learned before. Language Points 1. Linda likes serving in the army. army 作名词，意为“军队”，复数形式为 armies。 常见搭配：join the army（参军）、serve in the army（服兵役）、the army and navy（陆海两军）、regular army（正规军）。 e.g. He decided to join the army after graduation. （他毕业后决定参军。） 2. Mr Wu has taught in a primary school as a volunteer. primary 作形容词，意为“小学教育的；首要的；初级的”。 常见搭配：primary school （小学）primary cause（主要原因）、primary goal（首要目标）primary level（初级水平） e.g. Our primary task is to ensure everyone's safety.（我们的首要任务是确保所有人的安全。） 3. Since I started, I have helped out at over ten different sports events. help out 意为“分担工作；帮忙做”。 help (sb) out with sth 帮助某人处理某事 e.g. Can you help me out with the heavy boxes? （你能帮我搬一下这些重箱子吗？） I’ll help out with the party preparations. （我会帮忙准备派对。） 4. They were at a stadium for a charity match. charity 名词 1）表示 “慈善（行为 / 事业）”，为不可数 do charity（做慈善） charity work（慈善工作） out of charity（出于慈善） e.g. All the money raised will be donated to charity. （所有筹集的资金将捐给慈善事业。） 2）表示 “慈善机构 / 组织” ，可数，复数形式为 charities。 e.g. Several local charities are working together to help the victims.（几家当地慈善机构联手帮助灾民。） 本文件著作权为创作公司所有, 仅限于教师教学及其他非商业性和非盈利性用途。如发现盗用、转卖、网络传播等侵权行为, 本公司将依法追究其相应法律责任。 部分素材选自网络, 如有争议, 请联系删改。 声 明 $