情态动词基本用法.ppt

What are 情态动词(modal verbs)? 情态动词的特点 情态动词有一定的意义 无人称和数的变化 通常不带to ,后接动词原形 表示说话人的语气或情绪 情态动词备考方向: 1. 各情态动词的基本用法; 2. 易混淆情态动词的辨析; 3.情态动词在特定语境中的用法 4.虚拟语气中情态动词的用法. How many modal verbs can you remember? 1. can/could 1)表示能力 He can play table tennis quite well. 2) 表示事物一时的特征, 理论上的可能性 It’s always warm here, but sometimes it can be very cold. He’s good-tempered. However, he can be hard to deal with when offended. Even an experienced teacher can make mistakes. 3)表示许可/允诺 ---Can/Could Tom use the car? ---Yes , he can. You can have my seat. I am going now. 4) 表示推测 1) ---Someone is knocking at the door. Who can it be? Can it be Scarlet? ---No, it can’t be her. She called from Tokyo just now. 2) He can not have forgotten it. 3) The accident could have been avoided. 2. may/might 1)表示请求\许可 ---May/Might I come in? ---Yes, you may. 2)表示可能性的推测 Her appearance has changed so much that you may not recognize her. It’s so late. I think he may/might have gone to bed. You might have given him more help, but why didn’t you? 3) may用于祈使句表示祝愿 May you succeed! May you be happy! 3. must 1. 必须 Must I say “sorry”? Yes, you must. / No, you needn’t. You must see a doctor. 2. 猜测 “肯定,准是” She must be watching TV now. There must be some mistake. It must have rained last night. The ground is so wet. 3. “偏要,硬要” If you must smoke, please go out. 4. 否定,表示 “禁止” You mustn’t play with fire. You may hurt yourself. must对比have to 1) 两词都是‘必须’的意思，have to 表示客观的需要， must 表示说话人主观上的看法，即主观上的必要。 My brother was very ill, so I had to call the doctor in the middle of the night. He said that they must work hard. 2) have to有人称、数、时态的变化，而must只有一种形式。 He had to look after his sister yesterday. 3） 在否定结构中： don‘t have to 表示“不必” mustn’t 表示“禁止” You don‘t have to tell him about it. You mustn‘t tell him about it. 4.Shall的用法 (1). Shall 常用于第一人称表示简单的将来 When shall we meet again? I shall have finished my homework by Friday. (2) shall用于第二，三人称表示： 允诺或强烈的意志 It shall be done as you wish. You shall get a bike as your birthday pre