Unit 2 Healthy eatingPeriod 4 语法专题课学习目标1.Grasp the grammatical rules of ought to,need,dare,had better in this unit.2.Learn to use the modal verbs in real situations through self-study and practice.学习过程一、语法聚焦(一)情态动词的基本用法:1.ought to(1)Humans ought to (should) stop polluting nature.人类应该停止污染大自然了。(2)Prices ought to come down soon.价格可能会很快下跌。(3)You ought to have come earlier.你本该来得早一点儿。(4)They ought to go and see Mary tomorrow,but I don’t think they will.他们明天按理说应该去看看玛丽,但是我认为他们不会去的。(此句不宜用 should)(5)He ought to go now,oughtn’t he?他现在该走了,是吗?ought to 用法小结:(1) (2) (3) (4)ought to 与 should 的区别 (5)ought to 的否定形式为 2.need(1)—Need you go so early?你需要这么早走吗?—Yes,I must. 是的,我必须走。/No,I needn’t.不,不必。(2)You needn’t have bought it.你没有必要买(它)的。(但已经买了) (3)You don’t need to be so worried.你不必如此担心。(4)Do I need to say my telephone number again?我还需要再说一遍我的电话号码吗?need 用法小结:(1) (2)need 后接完成时表示“ ”。 (3)need 用作实义动词时, 3.dare (1)My younger sister dare not go out alone.我妹妹不敢单独出去。(2)If you dare cheat in your exam,I will give you some punishment.如果你(们)敢在考试中作弊,我就惩罚你(们)。(3)She dares to go there alone.她敢一个人去那里。(4)He did not dare (to) leave his car there.他不敢把车停放在那里。dare 用法小结:(1)dare“敢;敢于”,dare 用作情态动词时,具有四个特点:第一, 第二, ;第三, ;第四, 。 (2)dare 用作实义动词时, 4.had better(1)You’d better go to see a doctor.你最好去看看医生。(2)You’d better not disturb him.你最好别去打扰他。(3)How had we better go there?我们最好怎么去那儿呢?(4)Hadn’t we better take an umbrella?我们是不是带把雨伞比较好?had better 用法小结:(1) (2)如何构成否定句和疑问句: (3)在否定疑问句或反意疑问句中 (二)情态...
