Unit4 Grammar&Word power 课件 2026-2027学年译林版八年级上册

Grammar & Word power Unit 4 DIY fun By the end of this lesson, we will be able to： Use imperative sentences to give instructions, make requests and make suggestions. Apply the target grammar to talk about DIY activities in real situations. Use should / shouldn’t and had better (not) to give advice. 1 2 3 Form adjectives with opposite meanings by using the prefixes un-, in- and im-. 4 Learning objectives Grammar B Word power Practices Grammar A Summary Homework Lead in They are imperative sentences（祈使句）. Look at the sentences. What kind of sentences are they? Look and say Stand up. Sit down, please. Be quiet. Let’s go to school. Do not wash in hot water. Never give up. Be careful! Please keep quiet No smoking Do Not litter Grammar B Word power Practices Grammar A Summary Homework Lead in Read and think A Imperative sentences 表示客气和礼貌 表示否定 表示建议一起做 What do these sentences have in common? What are they used for? They don’t have a subject（主语）. We use them to tell people what to do or what not to do. Work out the rule don’t please let’s Take notes 祈使句 一、定义 用于表达命令、请求、劝告、警告、禁止等的句子叫作祈使句。 二、特征 主语为第二人称you，因动作指向明确，通常省略不写。 无人称、时态和数的变化 加上please更为客气和礼貌（please用在句末，常用逗号隔开） Take notes 三、祈使句的类型 类型 肯定形式 否定形式 Do型 动词原形（+宾语）+ 其他 在句首加Don’t 或Do not Be型 Be + 形容词/名词 + 其他 在句首加Don’t 或Do not Let型 Let + 宾语 + 动词原形 + 其他 1. Don’t let+ 宾语+动词原形+其他 2. Let +宾语+not+动词原形+其他 No型 / No + 名词/动词-ing形式 表示向对方提出建议 多表示公共警示语 never 代替don’t/ do not用于加强语气。 e.g. Never give up! Take notes Do型：动词原形（+宾语）+ 其他 Open the door. 否定： 更礼貌： Don’t open the door. Please open the door. Open the door, please. please位于句末时，常用逗号与其余部分隔开。 Be型：Be + 形容词/名词 + 其他 Be your own hero. Be careful! Don’t be afraid to make sentences. 否定句首加Don’t 否定句首加Don’t Take notes Let型：Let + 宾语 + 动词原形 + 其他 Let children pick flowers in the park. 否定： Don’t let children pick flowers in the park. Let children not pick flowers in the park. No型：No + 名词/动词-ing形式 No photos! →Don’t take photos here. No smoking! → Don’t smoke here. 否定句首加Don’t， 或者动词前加not. 助记： 祈使句，并不难，动词原形放句前。 否定句，很简单，don’t站在动原前。 尊重对方有礼貌，please句首句末加。 No型更简洁、正式 Don’t型更口语、温和 Let’s 的否定Let’s not 四、祈使句的应答 回答肯定形式的祈使句一般用will， 回答否定形式的祈使句一般用won’t —Please remember to bring your homework tomorrow. —OK, I will. 好的，我会的。 —Don’t be late for school again. —Sorry, I won’t. 对不起，我不会的。 Take notes 五、拓展——祈使句+ and / or 祈使句，and + 好的结果 “做……，就会……” 祈使句，or + 坏的结果 “做……，否则就会……” Hurry up, ____ you will be late for the DIY club. Put on the gloves, ____ your hands will be safe. Don’t be impatient, ____ you will make mistakes. or and or Take notes Cut Write Draw Look try don’t give Keep Grammar B Word power Practices Grammar A Summary Homework Lead in Read and think B Using should and had better had better 表示否定 What are they used for? What form of the verb follows them? should not The base form of a verb （动词原形）. Giving advice and telling people what we think is best or the right thing to do. Work out the rule should had better should = 应该，语气较委婉，表示建议或忠告。 had better = 最好，语气较强，常暗示“如果不这样做，可能会有不好的结果”。 Which one is stronger in tone? had better is stronger than should. Take notes 当我们给他人提建议时，可以用should“应该”和had better“最好”，had better语气比should强一些。 后接动词原形，没有人称时态和数的变化。 should had better（缩写’d better） 含义 应该 最好 肯定 should + 动词原形 had better + 动词原形 否定 should not/ shouldn’t + 动词原形 had better not + 动词原形 例句 You should work harder. You shouldn’t stay up very late. We’d better leave before it rains. He had better not do that again. Take notes should 改祈使句 当should/shouldn’t 表示建议，且主语是 you 时，可改为祈使句。 注意：去掉主语 you 和 should / shouldn’t。 动词用原形开头。否定用 Don’t。 可以加 please 使语气更礼貌。 You should read the instructions first. → You should be careful. → You shouldn’t be late. → Read the instructions first. Be careful. Don’t be late. You should buy some to learn more about it. You should join a DIY club to learn more about it. You had better not begin your work without redaing them. You had better/ should not play with them when you do DIY jobs. You should be patient. You had better be careful when you use it. You should read them slowly and carefully. Useful expressions You should... You’d better... You shouldn’t... You’d better not... You should read the instructions carefully before you start. You’d better be careful when you use glue. You shouldn’t use too much paint. You’d better not play with scissors. You should keep your tools in a safe place. You’d better ask for help if you are not sure. Grammar B Word power Practices Grammar A Summary Homework Lead in Read and think The prefixes un-, in- and im- One of the most common prefixes for adjectives is un-. It means “not”. We add it to some adjectives to give them the opposite meaning. We can also use some other prefixes, such as in- and im-, to form new adjectives with the opposite meaning. 形容词最常见的前缀之一是‌un-‌，它的意思是“不、非”。我们把它加在部分形容词前，就能赋予这些词相反的含义。除此之外，我们还可以使用in-、im-等其他一些前缀，来构成带有相反含义的新形容词。 Take notes 前缀 构词规则 例词 un- 最常用，多用于英语本族词 unlucky, unusual, unhappy, unable, untidy, unfriendly in- 多来自拉丁语，常见于较正式的形容词 incorrect, incomplete, inactive, inexpensive, invisible im- in- 的变体，用于 p, b, m 开头的词前 impossible, impolite, impatient, imperfect, immoral, imbalance il- in- 的变体，用于 l 开头的词前 illegal, illogical ir- in- 的变体，用于 r 开头的词前 irregular, irresponsible, irrelevant 拓展 Practices uninteresting unsure unable unfriendly inactive impatient inexpensive imperfect Practices unusual impatient impossible untidy incorrect Grammar B Word power Practices Grammar A Summary Homework Lead in I. 用所给词的适当形式填空。 1. __________ (not be) afraid of making mistakes. 2. Please __________ (pass) me the scissors. 3. Let’s __________ (clean) the room first. 4. __________ (be) careful with the glue. 5. Please__________ (not play) with fire. 6. No __________(smoke). Ⅱ. 选择合适的词完成句子。 1. You _________ (should / shouldn’t) read the instructions first. It’s important. 2. You _________ (had better / had better not) start now, or you’ll be late. 3. You _________ (should / shouldn’t) go too fast. It’s dangerous. 4. You ___________ (had better / had better not) get too much paint on the brush. 5. Mum, you _________ (should / had better) clean the bird box first. Don’t be pass clean Be don’t play smoking should had better shouldn’t had better not should Ⅲ. 单项选择。 1. The sign “No ______” means you can’t talk here. A. talk B. talking C. to talk D. talked 2. _______ more, and you’ll improve your spoken English. A. Speak B. Speaks C. Speaking D. To speak 3. People _______ talk on a mobile phone while they are driving. A. shouldn’t B. needn’t C. must D. can 4. Mike, _______such a loud noise in the room. Your sister is sleeping. A. making B. to make C. don’t make D. make 5. You’d better ______ out late at night. A. not to stay B. not stay C. don’t stay D. not staying 6. — You’d better not play computer games for too long. — ______. A. Yes, I will B.Yes, I do C. No, I don’t D. Sorry, I won’t Ⅳ. 按要求完成句子。 1.Let’s go out. （改为否定句） → ______________________________ 2. Talk in the library. （改为否定句） → ______________________________ 3. Hand me the tools. （用 please改为礼貌请求） → ______________________________ 4. You should step on the grass. （用 had better改为否定句） → ______________________________ 5. Don’t park here. （改为No 型） → ______________________________ 6. We play basketball after school.（用let改写句子） → ______________________________ 7. You should keep the room tidy.（改为祈使句） → ______________________________ Let’s not go out. Don’t talk in the library. Please hand me the tools. / Hand me the tools, please. You had better not step on the grass. No parking. Let’s play basketball after school. Keep the room tidy. Grammar B Word power Practices Grammar A Summary Homework Lead in What we have learnt today Imperative sentences（祈使句） Do型：动词原形+ 其他 （否定句首加don’t） Be型：Be + 形容词/名词+ 其他 （否定句首加don’t） Let型：Let + 宾语+ 动词原形+ 其他 （否定句首加don’t或者动词前加not） （Let’s not） No型：No + 名词/动词ing should / had better should + 动词原形 （否定为shouldn’t） had better + 动词原形 （否定为had better not） The prefixes un-, in- and im- 加在形容词前构成反义 Grammar B Word power Practices Grammar A Summary Homework Lead in Must do Choose to do 1. Finish the Grammar A and Grammar B exercises in the workbook. 2. Write five DIY instructions and three pieces of advice using the target grammar. 1. Make a DIY poster with at least 5 imperative sentences and 3 sentences with should / had better. 2. Write a short passage about your DIY experience, using at least three words with un-, in- or im-. See you! $