Unit 2 Modal verbsHe can type 100 words within one minute. abilityYou must work hard to win the gold medal. necessityShe might get a ticket for the concert. possibilityYou may come in and sit down. permissionLook at following sentences, pay attention to the words in red.Modal verbs＊情态动词除了可以表示能力、必要、可能、 允许外，还可表达愿望、猜测等意 :Example:I will be a famous singer in the future. (wish)He must be at home now. (guess)Can you help me with my training? (request)Shall we do some exercise this morning? (suggestion)＊情态动词不能独立作谓语，其后必加动词 原形，共同构成复合谓语； Children should respect their parents.＊情态动词没有人称和数的变化； I/You/She/We can speak English.＊常见的情态动词有： can, could, may, might, will, would, must, have to, had better, shall, should, ought to, need, dare can & could1) 表能力 can 表能力时意味着凭体力或脑力或技术等可以做。 I can climb this pole. He is only four , but he can read. Fire can’t destroy gold. 2) 表可能性 Can the news be true? It can’t be true. What can he possibly mean? 3) 表示允许（和 may 意思相近）常见于口语。 Can (May) I come in ? You can’t smoke in the classroom. * Could 表过去的能力、可能和许可 （常用于间接引语） At that time we thought the story could not be true. I could swim when I was only six. Father said I could swim in the river. may& might 1) 表示请求、可以、允许 You may watch TV now. 2) 当回答由 may 引起的问题时 , 否定答语要用 must not, 表示“不许可”、“不应该”、“不行”。 May I come in? ( = can ) Yes, you may. No, you mustn’t. 3) 表建议（可和 as well 连用） You may as well stay where you are. might 1) 在间接引语中表过去的“可能”和“允许” She said that he might take her dictionary. ＊除在间接引语中外， might 一般不表示过去的“可能...
