Unit3&4 语法课件 情态动词& What's...like 辨析课件 2026-2027学年外研版英语 八年级下册

情态动词 What’s … like? 相关句式 单击此处编辑母版标题样式 单击此处编辑母版文本样式 第二级 第三级 第四级 第五级 单击此处编辑母版标题样式 单击此处编辑母版文本样式 第二级 第三级 第四级 第五级 单击此处编辑母版标题样式 单击此处编辑母版文本样式 第二级 第三级 第四级 第五级 单击此处编辑母版标题样式 单击此处编辑母版文本样式 第二级 第三级 第四级 第五级 单击此处编辑母版标题样式 单击此处编辑母版文本样式 第二级 第三级 第四级 第五级 单击此处编辑母版标题样式 单击此处编辑母版文本样式 第二级 第三级 第四级 第五级 单击此处编辑母版文本样式 第二级 第三级 第四级 第五级 情态动词的相关用法 情态动词是一类特殊的助动词，它本身没有完整的实义，不能单独作谓语，必须搭配后面的动词原形一起使用，用来表达说话人的情绪、态度：建议、必须、许可、能力、推测、义务等含义。 1. 后面必须接动词原形（to do /doing/done 都不可以） 2. 没有人称和数的变化（have to 除外！have to 有人称变化 has to） 例：He should… ✔；He shoulds…❌ 3. 变否定，直接在情态动词后面加 not 例：should → should not (shouldn’t)；must → must not (mustn’t) should / shouldn't 的基本用法 should 意为“应该”，用来提出建议、劝告，或表示责任、义务。 否定形式: shouldn't = should not，意为“不应该”，用来表示反对或劝告不要做某事。 You should drink more water. (你应该多喝水。) You shouldn't stay up too late. (你不应该熬夜太晚。) 句型结构 • 肯定句： 主语 + should + 动词原形 + 其他. • 否定句： 主语 + shouldn't + 动词原形 + 其他. • 疑问句： Should + 主语 + 动词原形 + 其他? Should I take an umbrella? (我应该带伞吗？) 回答:Yes, you should. / No, you shouldn't. should / shouldn't 的常见使用场景 1. 健康建议 You should eat more vegetables. You shouldn't eat too much junk food. 2. 环保建议 We should save water and turn off the tap. We shouldn't waste electricity. We should plant more trees. should / shouldn't 的常见使用场景 3. 学习建议 You should listen to the teacher carefully in class. You shouldn't copy others' homework. 4. 日常礼貌 You should say “thank you” when someone helps you. You shouldn't talk loudly in the library. must & mustn't 用法 must意为“必须”，用来强调主观义务、命令，语气强烈 肯定句形式: 主语 + must + 动词原形 + 其他 I must finish my homework first. 我必须先完成家庭作业。 mustn't（=must not），意为“禁止，不准”，用来表示严禁做某事（不是 “不必”） 否定句形式 You mustn't stay out late on school nights.上学日晚上你不准在外逗留很晚。 must & mustn't 用法 一般疑问句与回答 - Must I hand in the report today? 我必须今天上交报告吗？ - Yes, you must. 是的，你必须。 - No, you needn't / don’t have to. 不，你不必。 注意:must 一般疑问句否定回答不能用 mustn't！mustn't 代表 “禁止”。 使用场景 1. 校规家规：You must follow the school rules. 你必须遵守校规。 2. 禁止行为：You mustn’t spend too much time playing computer games. 情态动词 核心含义 侧重点 否定形式 must 必须 主观想法、说话人命令 / 要求 mustn’t 禁止 have to 不得不 客观外界压力，客观情况迫使 don’t/doesn’t have to 不必 must VS have to 辨析 1. I must stop watching TV.（我主观上觉得该停了） 2. I have to stop watching TV, because my mother asks me to go to bed. 我不得不关掉电视，因为妈妈叫我去睡觉。（外界客观要求） 9 should / shouldn't 与 must / have to 的区别  You should see a doctor. (建议) You must stop at the red light. (强制规则) I have to finish my homework today. (客观要求) should 表示“应该”，语气较弱，建议性，不做可能也没关系，只是不够好。 • must 表示“必须”，语气强烈，强制性，不做会有后果。 • have to 表示“不得不”，客观要求，外界压力。 can& can't 用法 can意为①能够、会（能力）；②可以（许可） 肯定句形式: 主语 + can + 动词原形 I can deal with my teenage problems by myself. can’t(=can not)，意为“①不能，不会；②不可以（不许可）” 否定句形式 主语 + can’t + 动词原形 You can’t give up when you meet difficulties. can& can't 用法 一般疑问句与回答 Can I ask you for some advice? 我可以向你寻求一些建议吗？ Yes, you can. / No, you can’t.must 一般疑问句否定回答不能用 mustn't！mustn't 代表 禁止”。 使用场景 1. 能力：Teenagers can learn to manage their time. 青少年可以学会管理时间。 2. 许可：You can ask your teachers for help. 你可以向老师求助。 3. 不允许：You can’t argue with your parents. 你不能和父母争吵。 may& may not 用法 may意为可以（委婉请求许可）；可能（推测），语气委婉客气 肯定句形式: 主语 + may + 动词原形 May I share my problems with you? 我可以和你倾诉我的烦恼吗？ may not，意为“不可以（委婉禁止）；可能不” 否定句形式 主语 + may not + 动词原形 You may not copy your classmates’ answers. 你不可以抄同学的答案。 情态动词 核心含义 语气 核心用法 should / shouldn’t 应该 / 不应该 较弱 提出建议劝告 must / mustn’t 必须 / 禁止 很强 主观命令、严禁 have to / don’t have to 不得不 / 不必 中等 客观外界压力要求 can / can’t 能够 / 不可以 中等 能力、普通许可 may / may not 可以 / 不可以 委婉客气 委婉请求、可能性推测 should /must/have to /can/may 综合对比总表 14 例1： You look tired. You ______ go to bed early. A. should B. shouldn't C. can D. may ✅ 解析： 看起来累了，建议早睡。答案：A 例2： You ______ waste water. It's important for life. A. should B. shouldn't C. must D. can ✅ 解析： 不应该浪费水。答案：B 例3： — Should I turn off the lights when I leave? — Yes, you ______. A. should B. shouldn't C. do D. can ✅ 解析： 肯定回答用Yes, you should. 答案：A 1. You look tired. You _____ go to bed early. A. should B. shouldn't C. can D. may 2. You ______ waste water. It's important for life. A. should B. shouldn't C. must D. can 3. — Should I turn off the lights when I leave? — Yes, you ______. A. should B. shouldn't C. do D. can 4. We ______ recycle paper and glass to protect the environment. A. should B. shouldn't C. could D. may A B A A 5. You ______ eat too much sugar. It's bad for your teeth. A. should B. shouldn't C. must D. can 6. You ______ take an umbrella. It's going to rain. A. should B. shouldn't C. may D. can 句型转换 · 按要求改写句子（每题2分，共10分） 1. You should drink more water. (改为否定句) ________________________________________________ 2. We should waste water. (改为否定句) ________________________________________________ B A You shouldn't drink more water. We shouldn't waste water. 3. Should I take a rest? (作肯定回答) ________________________________________________ 4. You should go to school on time. (改为一般疑问句) ________________________________________________ 5. We should turn off the lights. (对划线部分提问) ________________________________________________ Yes, you should. Should you go to school on time? What should we do? 结构：What is + 主语 + like? 📌两大询问场景（必考区分） 1. 询问【人的内在品质、性格】 翻译：……是什么样的人？ 回答：性格形容词（kind, friendly, quiet, strict…） —What’s your English teacher like? —She is kind and patient. What’s … like? 19 2. 询问【事物/天气的整体特征】翻译：……怎么样？ —What’s the weather like today? —It’s rainy. —What’s the film like? —It’s interesting. 💡关键笔记： like 在这里是介词，翻译：像……；不是动词“喜欢”！ What’s … like? 20 句型 提问侧重点 回答内容 What’s sb like? 性格、内在品质（也可兼顾外貌） kind, outgoing, quiet… What does sb look like? 只问外貌长相 tall, has long hair… How is sb? 询问身体状况/心情 Fine. / He feels sad. 相关句式总结 21 句型转化 复数形式：What are … like? —What are your classmates like? —They are helpful. 2. 同义转换： What’s the weather like? = How is the weather? 仅限天气场景通用！描述人不能互换 22 1. —____ your new neighbour like? —He is friendly and helpful. A. What does B. What’s C. How’s 2. —____ your sister look like? —She has big eyes and long hair. A. What’s B. How does C. What does 3. —____ the weather like today? —It’s sunny. A. How’s B. What’s C. What does 4. —How is your father? —____ A. He is hard-working. B. He is fine. C. He is tall. B C B B 23 5. —What’s the movie like? —____ A. It lasts 2 hours. B. It is exciting. C. I like it. 6. —____ your classmates like? —They are active. A. What are B. What’s C. How are 7. —What does Amy look like? —____ A. She is shy. B. She is thin. C. She likes dancing. 8. —____? —He is quiet. A. What does Tom like? B. What’s Tom like? C. What does Tom look like? B A B B 24 9. What’s the weather like? = ____ A. How is the weather? B. What does the weather look like? C. How does the weather like? 10. —What’s your PE teacher like? —____ A. He likes playing sports. B. He is strict but nice. C. He runs fast. 二、用 What’s…like / What does…look like / How is 填空（可变换形式） 1. —__ __ your grandma ____? —She is kind. A B What’s like 25 2. — ____ your brother ____? —He is tall with short black hair. 3. — ____ the park ? —It’s beautiful. 4. — your mother? —She is much better now. 5. — the girls ____? —They are outgoing. What does look like What’s like How is What are like 26 $