Unit 8 Section A（4a-4d）（同步教学课件） 2025-2026学年八年级英语下册同步教学精品课件（新教材人教版）

该初中英语课件聚焦现在完成时“未完成用法”，核心涵盖for与since的用法差异及延续性动词转换。课堂通过4a志愿者工作对话情境导入，引导学生观察总结语法规则，搭建从具体语境到抽象语法的学习支架，衔接基础用法深化对持续动作的理解。 其亮点在于融合思维品质（对比辨析for/since及动词类型）、语言能力（4b-4d从填空到访谈的应用链）和文化意识（志愿者情境渗透助人精神）。采用“观察-总结-应用”教学法，以“本课句型”系统梳理核心词句，助力学生提升语法应用与沟通能力，为教师提供素养导向的完整教学资源。

Section A 4a-4d Unit 8 Making a Difference Learning Aims 语言能力 文化意识 思维品质 学习能力 Master the usage difference between for and since; correctly use present perfect tense to describe lasting actions. Summarize grammar rules by observing sentences; finish exercises independently and apply knowledge in simple communication. Distinguish and compare language rules; judge proper tense usage in different contexts Understand the value of volunteer work andform the spirit of helping others.. 4a Read the sentences. How are for and since used differently? Have you been to our animal shelter before? Has she ever done volunteer work? How long have you been a volunteer? How long has he worked as a volunteer at the museum? No, I haven’t. But one of my friends has volunteered here for a long time. Yes, she has. She has been a volunteer at a nursing home since last August. I have been a volunteer here for a few months. He has volunteered here since his summer holidays started. 现在完成时 核心结构 have / has (助动词) + done (过去分词) 核心功能 过去某个时间发生的事，对现在产生影响。 过去存在的状态一直持续至今。 现在完成时的时间标志词及其用法 since 后接时间点，如 since 2023、since last August 等。 for 后接一段时间，如 for a long time、for three years 等。 since 后不仅可接表示时间的短语，也可接表示时间的状语从句，如 since I was born、since the summer holidays started 等。 现在完成时表示动作或状态从过去某时开始，一直延续至今，还可能继续下去。这种用法称为“未完成用法”。此时常与for 或 since 引导的时间状语（从句）连用。 1. 现在完成时的含义 现在完成时（二） 2. 现在完成时的“未完成”用法 表示“未完成”的句式 示例 现在完成时+for+一段时间 We have known each other for twenty years. 我们认识有二十年了。 现在完成时+since+表示过去的时间点 Mr. Smith has worked here since 1984. 自从1984年史密斯先生就在这里工作。 现在完成时+since+从句 I have lived here since I was born. 我从出生起就住在这儿。 3．延续性动词与非延续性动词 （1）含义：延续性动词表示能够延续的动作，这种动作可以延续下去或产生 持久影响。非延续性动词也叫终止性动词、瞬间动词等，表示不能延续的动作，这种动作发生后即刻停止。 （2）用法： ①常见的延续性动词有 learn、work、live、know、walk、watch、sleep、stay、wait、keep 等。 延续性动词可以与表示一段时间的状语连用，如 how long、for+时间段、since+过去的时间点、since 引导的时间状语从句（一般过去时）、since+一段时间+ago 等。 （2）用法： ②常见的非延续性动词有 open、close、die、begin、come、go、borrow、lend、buy、move 等，表示某个动作的结果还存在，但不能与表示一段时间的状语连用。有些非延续性动词可以用延续性动词替换。 ③在否定句中，非延续性动词可以与表示一段时间的状语连用。 e.g. I haven’t heard from my friend for three weeks. 我已经有三个星期没有收到我朋友的来信了。 （3）非延续性动词转换为延续性动词的方法： ①将非延续性动词转化为“be+形容词或副词”，这样才能和时间段连用： begin/start →be on（开始） go there →be there （去那里） come back →be back（回来） come here →be here （来这里） open →be open（开业） close →be closed （关门） die →be dead（死） marry →be married （结婚） finish →be over （结束） go to bed →be in bed （上床睡觉） leave →be away （离开） return →be back （回来） get out →be out （出去） fall asleep →be asleep （入睡） lose →be lost （丢失） fall ill →be ill （生病） get/arrive/reach →be in/at （到达） join/become →be in/be a member of （参加，加入） （3）非延续性动词转换为延续性动词的方法： 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’ve made a lot of friends ______ I joined the organization. have been since have taught for Complete the sentences with the correct forms of the verbs in brackets and for or since. 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. for has helped has trained Since since 4c 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 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. have worked have helped have made have met met was got smiled thanked 4d Work in groups. Interview your groupmates using the questions below. Share the answers with the class. known your best friend/. . . ? had your favourite toy/. . . ? lived in your neighbourhood/. . . ? How long have you 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.... Group work Work in groups. One student acts as an interviewer to interview others and complete the chart. Then report. Students Things How long Tony favorite book for two years basketball since he was 10 years old Student 1 Student 2 Language points Point 1 have been to/ have gone to/ have been in have been to have gone to have been in "曾经去过", 说话时已不在去过的地方, 常与ever/never等连用。后可接次数，表示"去过某地几次". "去了某地",表示到了某地或正在去某地的途中,该人不在现场，一般不用第一/二人称作主语. 表示在某地待了多久, 常跟"for+一段时间"连用. 用how long 进行提问. He has been to Beijing. 去过北京 He has gone to Beijing. 去了北京 He has been in Beijing for 3 years. Point 2 Mr Wu has taught in a primary school as a volunteer for two years now.作为志愿者吴先生现在已经在一所小学任教两年了。 primary adj. 小学教育的；首要的 (1)adj.小学教育的，用于名词前作定语。 primary school小学 primary education小学教育 For middle and primary school students, learning to cook has become a must. 对于中小学生来说，学习烹饪已经成为必须要做的事。 (2)adj.首要的 Personal safety is of primary importance. 人身安全至关重要。 Point 3 They were at a stadium for a charity match. 他们正在体育场参加一场慈善比赛。 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） 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。 Several local charities are working together to help the victims. 几家当地慈善机构联手帮助灾民。  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 （如：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） Point 4 Exercises 单项选择 一、用括号内所给词的适当形式填空。 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 B C 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 D 4. - Have you two each other before, Ken? - Of course. Tim and I friends since 4 years ago. A. meet; become B. met; become C. meet; have been D. met; have been D 5. The professor reached Nanjing last Wednesday. He there for10 days. A.has been B. has got C.has reached D. has arrived 6. Many international students visit our school since last year. A. are coming B. have come to C. came D. will come B A 二、用所给词的适当形式填空。 1. Jeff ________ (have) this toy plane for more than ten years. 2. Jill ________ (borrow) the book last week and she ________ (keep) it for six days. 3. I ______________ (not see) him since I met him at the airport three years ago. has had borrowed has kept haven’t seen 4.Recently, more and more people ______________ (choose) to visit Yangzhou during holidays. 5. We ______________ (not meet) each other for five years. Both of us ______________ (leave) our hometown five years ago. have chosen haven’t met left 6. How long you _________ (know) Mr. Smith? 7. Mike and his parents (be) the north for half a year. 8. Mum is not at home now. she (go) the shop. 9. - ______ you ever (be) kunming ? - Never. 10. - Has Jim arrived yet? - Yes, he (be) here for several days. have known have been in has gone to Have been to has been 11. Recently，more and more people have (choose ) to visit Yangzhou during holidays. 12. I have (regret )never choosing to be kind, even when it was not easy. 13. Mr. Zhang is an experienced teacher. He has (teach ) geography for overthirty years. 14. -Do you know Mount Wudangin Shiyan? -Yes, I have (climb) it twice. It's fantastic. 15. 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 三、句型转换 1. He left his hometown in 2018. He is still away now. → He ______ ______ ______ from his hometown ______ 2018. 2. I borrowed this book last week. I still have it now. → I ______ ______ this book ______ last week. 3. The film started ten minutes ago. It is still on now. → The film ______ ______ ______ for ten minutes. has been away have kept has been on since since 4. She joined the music club in 2022. She is still a member now. → She ______ ______ ______ the music club ______ 2022. 5. They moved to this city 5 years ago. They still live here now. → They ______ ______ in this city ______ 5 years. 6. My grandpa died in 2021. He has been dead for 5 years.（仿照例句改写） → My grandpa ______ ______ ______ since 2021. 7. I bought this phone in 2024. I still use it now. → I ______ ______ this phone ______ 2024. has been in have lived has been dead have had since for since 8. The film began ten minutes ago. The film _____ ____ ____ for ten minutes. 9. The dog died two days ago. The dog _____ ______ _____ for two days. has been on has been dead 10.He joined the army in 1985. He _____ _____ ____ the army ____ 1985. 11.The movie started ten minutes ago. The movie _____ _____ ____ for ten minutes. has been in since has been on 12.The bus left five minutes ago . The bus _____ already ____ _____ for five minutes. 13.The girl bought a new school bag in September. The girl ____ ____the school bag since September. 14. The shop closed last winter. The shop ____ ____ ______ since last winter. has been away has had has been closed 2. 琳达的父亲自2000年就在一所小学工作。 Linda’s father _______________________________since 2000. 3. 上周末我们学校组织了一场慈善比赛，为贫困儿童筹款。 Our school organized a __________ __________ last weekend to raise money for poor children. has worked in a primary school charity match 四、根据汉语意思完成句子。 1.我的哥哥自从2022 年起就参军了。 My brother ______________________________ since 2022. has been in the army 4. 那位老人热情地感谢我们帮他过马路。 The old man ________ ________ ________ for helping him cross the road. 5. 我已经在我爷爷的农场帮忙三天了。 I ________ ________ ________ on my grandfather’s farm for three days. thanked us warmly have helped out 本课句型 Summary 我都 学会了! Key words Expression army soldier primary charity warmly help out 1. She has taught English to the soldiers for three years. 2. I have been a member of the Red Cross for six years since I joined the organization. 3. Mr Wu has taught in a primary school as a volunteer for two years now. 4. Since I started, I have helped out at over ten different sports events. Sentences Basic (必做) 用when/while各造2个句子，连接一般过去时与过去进行时。 Improving(选做) 2.编写一段50词小短文，描述“暴风雨来临时家人正在做的事”，至少用3个过去进行时句子。 Extend (选做) 3.整理when与while用法区别，用英文写出3条规则，并各举1个课本例句。 Homework Thank you ! $