Unit 6 语法讲解及习题：have to, had better, needn’t, used to 2025-2026学年沪外教英语七年级下册

沪外教英语七下Unit6语法讲解及习题 have to, had better, needn’t, used to 一、核心语法讲解 本单元核心语法为情态意义的高频结构:have to(必须/不得不)、had better(最好)、needn’t(不必)、used to(过去常常),贴合“文学经典与阅读习惯”话题,用于表达必要性、建议、过去习惯与现在的对比,具体解析如下: (一)核心结构与用法总表(核心考点) 结构 核心含义 时态/人称变化 否定形式 疑问形式 关键特征 have to 客观必要性(外界要求/规则) 有变化: 一般现在时:have/has to 一般过去时:had to don’t/doesn’t have to(不必) (≠ mustn’t 禁止) Do/Does + 主语 + have to...? Did + 主语 + have to...? 强调“客观被迫”,无“必须”的主观意愿 had better 强建议(“最好……”,否则有不良后果) 无变化: 所有人称均用had better had better not(最好不要) Had + 主语 + better...? (口语中极少用,常用陈述句) 后接动词原形,had 无过去含义,表现在/将来 needn’t 不必要(“不必”) 无变化(情态动词用法) 本身表否定,无需加not Need + 主语 + 动词原形...? 直接接动词原形,对应 don’t have to used to 过去常常(现在已不如此) 无变化 didn’t use to Did + 主语 + use to...? 后接动词原形,强调“过去与现在的对比” (二)分点详解与例句 1. have to(客观必要性) 用法:因规则、责任、客观条件而“必须做某事”。 例句: a. We have to finish reading Charlotte’s Web this month for the book report.(为了读书报告,我们这个月必须读完《夏洛的网》。) b. Does he have to look up every new word in the dictionary?(他必须每个生词都查字典吗?) c. They don’t have to read the whole book at once—they can read it part by part.(他们不必一次性读完整本书,可分部分阅读。) 2. had better(强建议) 用法:给他人提建议,语气比 should 更强,隐含“不这样做会有麻烦”。 例句: a. You had better read classic books slowly to understand the deep meaning.(你最好慢读经典,以理解深层含义。) b. We had better not judge a classic book by its cover.(我们最好不要以封面评判经典书籍。) 3. needn’t(不必要) 用法:表示“做某事不是必须的”,与 don’t have to 同义,语气更委婉。 例句: a. You needn’t memorise every sentence in the classic—just understand the main idea.(你不必背诵经典里的每句话,理解主旨即可。) b. Need I finish the essay today?(我今天必须写完这篇随笔吗?) 4. used to(过去常常) 用法:描述过去持续的习惯或状态,现在已停止,常与 but now 连用形成对比。 例句: a. I used to read adventure stories, but now I prefer classic novels.(我过去常读冒险故事,但现在更喜欢经典小说。) b. He didn’t use to like poetry, but now he reads it every day.(他过去不喜欢诗歌,但现在每天都读。) (三)核心易错点辨析 1. don’t have to vs mustn’t don’t have to:不必(做不做都可以) You don’t have to read this chapter.(你不必读这一章。) mustn’t:禁止(绝对不能做) You mustn’t write on the classic books.(你禁止在经典书籍上写字。) 2. used to vs be used to 本单元仅考 used to do(过去常常做); 易混点:be used to doing(习惯于做)、be used to do(被用来做),本单元暂不涉及,需明确区分。 3. had better 的时态 had better 中的 had 是固定搭配,不表过去,不能改为 has better 或 have better。 二、语法习题 题型一:选词填空(从 have to/has to/had better/needn’t/used to 中选择,注意形式变化) 1. We _ read the introduction of a classic first to know its background. 2. My little sister _ like classic books, but now she loves them. 3. You _ rush to finish the book—take your time to enjoy it. 4. He _ look up every new word because his English is very good. 5. She _ finish the book report today, or she will be punished by the teacher. 6. We _ not read in the sun—it’s bad for our eyes. 7. Did you _ read a lot of fairy tales when you were a child? 8. The students _ prepare a presentation about their favourite classic writers. 9. You _ choose a classic book that interests you, or you won’t stick to reading it. 10. He _ live in a small town where he first read Tom Sawyer. 11. Do they _ read the whole novel, or just a part of it? 12. You _ worry about the difficult words—you can guess their meanings from the context. 题型二:单句改错(每句1处错误) 1. You had better to read more classics to improve your writing. _ 2. He doesn’t used to like poetry, but now he writes it himself. _ 3. We mustn’t finish the book today because it’s too long—we can do it tomorrow. _ 4. She has to not stay up late reading classics; it’s bad for her health. _ 5. Did he use to reading adventure stories when he was young? _ 6. Everyone had better chooses a classic book for the reading club. _ 题型三:单项选择 1. — _ I finish reading Journey to the West this week? —No, you _ . You can finish it next week. A. Must; mustn’t B. Need; needn’t C. Have to; don’t have to D. Had better; hadn’t better 2. I _ read picture books, but now I prefer reading classic novels. A. used to B. have to C. had better D. needn’t 3. You _ take notes while reading classics, or you will forget the key details. A. needn’t B. had better C. don’t have to D. used to 4. She _ look up every new word because she has a good English dictionary. A. hasn’t to B. doesn’t have to C. mustn’t D. hadn’t better 5. —What do you think of my book report? —You _ correct the spelling mistakes before handing it in. A. used to B. have to C. had better D. needn’t 6. He _ play outside after school, but now he stays at home reading classics every day. A. didn’t use to B. used to C. has to D. needn’t 7. You _ read the book word by word—just catch the main idea. A. needn’t B. had better C. have to D. used to 8. The students _ prepare for the classic reading competition next month. A. had better B. used to C. have to D. needn’t 9. —Did she _ like Charlotte’s Web? —No, she didn’t. But now it’s her favourite classic. A. use to B. have to C. had better D. needn’t 10. You _ not read in the library—keep quiet, please. A. needn’t B. mustn’t C. don’t have to D. didn’t use to 题型四:句型转换 1. I used to read adventure stories every weekend.(改为否定句) 2. We have to finish the book report by Friday.(改为一般疑问句并作否定回答) 3. You had better read classic books slowly.(改为否定句) 4. He needs to look up the new word in the dictionary.(改为同义句,用 needn’t) He _ _ look up the new word in the dictionary.(改为否定句) 题型五:完成句子 1. 我们不必每个生词都查字典,因为可以从上下文猜测意思。 We _ _ look up every new word in the dictionary because we can guess their meanings from the context. 2. 鲁迅过去喜欢读古代英雄的故事,这对他后来的写作产生了很大影响。 Lu Xun _ _ enjoy stories about ancient heroes, and this had a great influence on his writing later. 三、习题答案与解析 题型一:选词填空 1. had better(解析:提建议,建议先读引言了解背景) 2. didn’t use to(解析:与 now 对比,过去不喜欢,现在喜欢) 3. needn’t(解析:建议慢慢来,不必匆忙) 4. doesn’t have to(解析:英语好,不必查每个生词,主语单数) 5. has to(解析:客观要求,否则受罚,主语单数) 6. had better(解析:强建议,不要在阳光下读书) 7. use to(解析:一般疑问句,Did 后接动词原形 use) 8. have to(解析:客观任务,准备展示,主语复数) 9. had better(解析:提建议,选感兴趣的书才能坚持) 10. used to(解析:描述过去的居住状态) 11. have to(解析:一般疑问句,Do 后接动词原形 have) 12. needn’t(解析:不必担心生词,可猜词义) 题型二:单句改错 1. 去掉 to(解析:had better 后接动词原形,不能加 to) 2. doesn’t didn’t(解析:used to 的否定式是 didn’t use to,助动词后用原形 use) 3. mustn’t don’t have to/needn’t(解析:句意是“不必今天完成”,mustn’t 表禁止,不符合语境) 4. has to not doesn’t have to(解析:have to 的否定式是 don’t/doesn’t have to,not 不能放在 have to 中间) 5. reading read(解析:used to 后接动词原形,Did 后也需用原形 read) 6. chooses choose(解析:had better 后接动词原形) 题型三:单项选择 1. B(解析:问句用 Need 表“必须”,答句 No 对应 needn’t(不必);A 项 mustn’t 表禁止,错误;C 项 Have to 不能用于句首提问,错误;D 项 had better 不用于疑问句,错误) 2. A(解析:与 now 对比,表过去常常,用 used to) 3. B(解析:提建议,不做笔记会忘细节,用 had better) 4. B(解析:不必查每个生词,have to 的否定式是 doesn’t have to;A 项 hasn’t to 为错误形式) 5. C(解析:提建议,交之前改拼写错误,用 had better,语气比 have to 更贴合语境) 6. B(解析:与 now 对比,过去常出去玩,用 used to) 7. A(解析:不必逐字读,只需抓主旨,用 needn’t) 8. C(解析:客观要求,准备比赛,用 have to) 9. A(解析:Did 后接 use to,表“过去常常”) 10. B(解析:图书馆禁止喧哗,用 mustn’t;needn’t 表不必,不符合语境) 题型四:句型转换 1. I didn’t use to read adventure stories every weekend. 2. Do you have to finish the book report by Friday? — No, we don’t. 3. You had better not read classic books slowly. 4. He needn’t look up the new word in the dictionary. 题型五:完成句子 1. needn’t / don’t have to 2. used to ( 1 ) 学科网(北京)股份有限公司 $