Unit 1 Food for Thought Using language 语法课件-2025-2026学年高中英语外研版必修第二册

情态动词 Modal Verbs 主讲人： 时间： 动词的分类 01 连系动词 03 助动词 02 情态动词 04 实义动词 动词的分类 用法 实义动词 也叫行为动词，表示具体的动作、行为或状态，具有完整的词汇意义，可以独立充当句子谓语。 连系动词 也叫系动词，本身有一定词义，但不能独立充当谓语，必须与后面的表语一起构成“系表结构”，用以说明主语的身份、性质、特征或状态。 助动词 助动词本身没有实际词汇意义，不能独立作谓语，必须与主要动词（实义动词或系动词）的原形或分词形式一起使用，以帮助构成疑问句、否定句、时态、语态等语法结构。 情态动词 情态动词表示说话人对动作或状态的态度、看法或推测（如可能、必须、应该、能够等）。它们有一定的词义，但不完整，必须与动词原形一起构成谓语。 [举例] I cook every day. I have to cook every day. 情态动词用法 [一、Can, Could的用法] 该单词有三种意思： 表示能力 表示请求 表示推测 [表示能力] can一般指体力、知识、技能等方面的能力，即“能够，会” could表示过去的能力 [举例] Can you swim? -Yes, I can./ No, Ican’t. I couldn't speak well until I was five years old. [小结] can 表示“能够,许可”,只用于现在时和过去时,而be able to 表示“经过努力而能够做某事”,可用于多种时态。 [表示请求，允许] You can/may take both,if you want. -Could you help me with the housework? -Yes,I can. You can't park your car there. [表示推测] -Who can/may it be? It is so late -Could you help me with the housework? -It can't be Ivy. She won't be back that time in the evening. [二、may, might的用法] 该单词有三种意思： 表示请求许可，可以； 表示推测，可能； 表示祝愿 [表示请求，允许] may和might 表示“许可”时,比can和could 更正式。 You may come if you wish. May I borrow your newspaper? Students may not stay out after midnight. [表示推测] may表示的可能性比can小,而might既可以作may的过去式,也可以替代may说明现在的情况,可能性比may更小。 即can大于may,may大于might的可能性。 [举例] He may have missed his train. He might get there on time, but I can't be sure. [表示祝愿，在正式场合或书面语中表示祝愿时,常放在句首] May you succeed! [三、must, have to的用法] must有两种意思： must必须；否定形式为needn’t。mustn't的意思是禁止 must一定；否定形式为can't [举例] I must go and get the kids from school. You mustn 't say things like that. I have to leave now. My mom is expecting me. You don 't have to get up early . 表示必须 [举例] -Must I go with them? -Yes, you must. -No, you needn't/don't have to. 表示“必须”时,含有must的问句,其肯定回答仍然用must,否定回答则用needn't或 don't have to [举例] Ivy must fail the exam. She keeps crying. It must be Father. He always gives me surprises. It can't be Father. He hasn't returned from work. 表示一定 [四、shall的用法] 仅作了解 表示征求对方意见（多用一，三人称） Shall we go out for a walk? [五、should的用法] 该单词有两种意思 1.应该，应当 2.推测 [举例] You should do it because you promise to. You shouldn't watch TV every day. 1.“应当，应该”，可用于各种人称 [举例] They should arrive at noon. Mary should be there by now. 2.表示推测 表示说话者根据一定的依据对某种情况进行推测,意为“(按理说)应该” [六、will、would的用法] 该单词有两种意思 1.请求 2.意愿 [举例] Will you give her the letter? Would you open the door, please? 1.表示请求 will 和 would 表示请求时,一般用于主语是第二人称的问句中,此时,二者可通用,但 would 比 will 更委婉(would 不表示过去)。 [举例] I will help you if you meet with trouble. Mary said she would try her best to help me. 2.表示意愿 表示自愿做或主动提出做某事,will表示现在的意愿,would 表示过去的意愿。 [七、used to的用法] 1.基本用法。 used to意为“过去常常,过去是”,其后跟动词原形,表示过去存在的某种状态或过去某种经常性、习惯性的行为或动作,并意味着这种情况目前已不复存在,侧重于过去与现在的对比。used无人称和时态的变化。 be uesd to doing sth I’m used to taking a walk after dinner. I used to play football when I was a child. They used to go there every year. I used to go to bed at nine in the evening, but I usually go to bed at ten now. Rachel is not what she used to be. [举例] [八、had better的用法] “最好” You'd better go to the doctor about your cough. If you think it is going to be easy, you'd better think again. had better的否定形式是在better后加not,疑问形式是把had提至主语前 . You had better not do that again. . Had I better go now? [举例] [九、need的用法] 该单词既可以做情态动词：需要 也可以做实义动词：需要 1. need做情态动词 常用于否定句、疑问句和条件句中。 对疑问句的肯定回答用must,否定回答用 needn’t Need I tell him everything that has happened to his family -Yes, you must. -No, you needn't. You needn't come so early. I'll lend Ivy the money if she need use it right now [举例] 2. need做实义动词 I need to drink some water. -Do I need to leave my luggage? -Yes, you need to. -No, you don't need to. . All living things need water. [十、dare的用法] dare作情态动词时，多用于疑问句、否定句、条件句中。 你只需要知道其意思是“敢”即可 Dare he tell his teacher what he knew? The thief ran away and dared not/ daren't come back. You will be punished if you dare break the rules. [举例] [练习] [练习] [练习] [练习] [练习] [练习] Thank you 主讲人： 时间： $