人教版七年级英语下册Unit4第2课时（AGrammarfocus-3c）优质课件 35页

R·七年级下册 Unit 4 Don’t eat in class. Grammar focus-3c Lead-in Tell others about your school rules. (You can finish it by yourself/ with your partner. ) listen to music In our school, we can’t listen to music in class, but we can listen to it after class. In our school, we can’t listen to music in class, but we can listen to it after class. What are the rules in your school? Role-play Can you eat in the classroom ? No, we can’t. We have to eat in the dining hall. And it’s important not to be late for class. Yes, so you must be on time. Grammar Focus Don’t run in the hallways. Don’t fight. What are the rules? Can we eat in the classroom? We must be on time for class. No, we can’t, but we can eat in the dining hall. Can we wear a hat in class? Does he have to wear a uniform at school? What do you have to do? Yes, we can./ No, we can’t. Yes, he does./ No, he doesn’t. We have to be quiet in the library. 祈使句的用法 1.祈使句的概念 (1)祈使句是指用来表示请求、命令、叮嘱、 建议等的句子。祈使句没有主语，谓语动 词 用原形，句末使用感叹号或者句号。例：站起来！ 一定要准时。 （命令） (叮嘱) Stand up! Be sure to be on time. (2)如果祈使句表示客气地请求，一般要加上please。 please可以放在句子前面也可以放在句子的后面。 例: 请跟我读。 Please read after me. （请求） = Read after me, please. 2.祈使句的形式 (1)let开头的祈使句的肯定句：Let + sb.+ v.（原形） 例: 让我们帮助你。 Don’t let them come in. Let us help you. 否定为：Don’t + let + 第三人称代词+v.（原形） 例: 不要让他们进来。 (2)非let开头的祈使句的肯定句和否定句： 肯 定 句 Do 型 Be 型 动词原形（+宾语）+其他成份. Be+表语(名词或形容词）+其他成份. 例：Listen to me, please. 例：Be quiet, please. 请听我说。 请安静。 否 定 句 Don’t +行为动词 +其他. Don’t + be +其他. No + n./v.-ing. 例: Don’t play computer games. 例: Don’t be late again. 例: No photos. No swimming. 不要玩电脑游戏。 不要再迟到。 不许拍照。 不许游泳。 3.祈使句的用法 主语是you常省去，动词原形开头记。 否定形式要注意，句首要把don’t加。 要讲客气用please， 句首、句末没关系。 情态动词must与have to 1.情态动词must的用法 (1)表示做某一个动作的必要和义务，意思是 “必须、应该”。 例:你必须做你的作业。 You must do your homework. (2)表示有很大把握的判断或者推测，它的意思是 “一定、准是”。 例:那个高个子男人一定是你的爸爸。 The tall man must be your father. (3)以must开头的一般疑问句，它的否定回答用 needn’t (不必要),不用mustn’t(不允许) ,mustn’t 常用于否定句中，表示“不允许，禁止”。 例:你的车不允许停在这儿。 You mustn’t park your car here. 2.情态动词have to的用法 have to表示客观需要做的事情，意思是“必须， 不得不”。 (1)have to后接动词原形，意为“必须做……；不 得不做……”。 例: 我不得不离开了。 I have to leave. (2)have to有人称、数和时态的变化，其第三人称 单数形式为has to。 例: 她不得不做作业。 She has to do her homework. (3)含有have to, has to的句子变疑问句或否定句需 分别借助助动词do, does 。 例: 他们必须早起吗？ Do they have to get up early? Do you know the meanings of these signs? No talking! Can we talk in the library? We can’t talk in the library. Don’t talk! We must keep quiet in the library. You can’t bring your school bags in the library. Don’t bring your school bags. We can’t bring umbrellas. Don’t bring your umbrellas. Don’t eat food. You can’t eat in the library. You can’t listen to music. Don’t listen to music. Write the rules for the school library.3a Library Rules 1.__________________ 2.__________________ 3.__________________ 4.__________________ Don’t talk. Don’t eat or drink. Don’t listen to music. Don’t take photos. Use the words to make questions about the rules. Then write answers according to your school.3b 1. Be quiet? (she/have to /in the library) Q: Does she have to be quiet in the library? A: Yes, she does. 2. Eat? (he/have to/in the dining hall) Q: _________________________________________ A: _________________________________________ Does he have to eat in the dining hall? Yes, he does. 3. Listen to music? (we/can/in the hallways) Q: _________________________________________ A: _________________________________________ 4. Wear a hat?(we/can/in the classroom) Q: _________________________________________ A: _________________________________________ Can we listen to music in the hallways? No, we can’t. Can we wear a hat in the classroom? No, we can’t. Make up five cool rules for your dream school. Share your rules with the class. Your classmates vote for the Coolest School! 3c 1. We can eat in class. 2. We don’t have to come to school every day. 3. … At my dream school, we don’t have to come to school every day. We can eat in class. We … 拓展 Write a letter to your parents about the rules at home. Let them know your ideas. For example： Be friendly. Save water. Don’t go out at night. Don’t eat in the bed. Don’t sleep too late. Don’t waste money. Don’t talk loudly. Don’t keep animals. Don’t talk loudly on the phone. Don’t watch TV late at night. Clean the bedroom on Saturdays. Don’t get up late on Sundays. Don’t talk loudly at night. Dear parents, I know you love me very much. Now I’ve grown up(长大). We should respect (尊重)each other. I have some suggestions(建议)for you. _______________________________________ _______________________________________ _______________________________________ Will you listen to me? Language points 1. We don’t have to come to school every day. 我们不必每天来学校。 have to为固定短语，意为“不得不，必须”， 其后接动词原形，有时态和人称的变化。 have to的否定形式是：主语+don’t + have to+动 词原形+其他（一般现在时，当主语是第三人称单 数时,用doesn’t have to，一般过去式用didn’t have to) Summary 语法 1. 祈使句的三种类型用法 Don’t run in the hallway. 2. 情态动词can, must, have to的用法 Can we wear a hat in class? We must be on time for class. We have to be quiet in the library. 把下列祈使句改成否定形式。 1. Be on time. 2. Eat in the hall. _____________________ _____________________ 3. Talk loudly. _____________________ Don’t be on time. Don’t eat in the hall. Don’t talk loudly. Exercise 单项选择。 1. ______ with fire. It’s very dangerous. A. Playing 　 B. Play C. Don’t play D. Doesn’t play 2.The children _____ play football on the road. A. can 　　B. must 　 C. mustn’t 　 D. may 3.My sister ______ be at school by seven o’clock. 　A. has to　　　 B. have to 　　　 C. had to 　　　 D. must to 4. It’s raining all day, so my brother ______ stay at home. 　A. must 　B. have to　　C. must to 　D. has to