（新教材）2020外研版英语新素养导学必修二课件：UNIT 1 USING LANGUAGE .ppt

1、Unit 1Food for thoughtUsing language情态动词(1)【语用功能】情态动词表示说话人对某一动作或状态的看法或主观设想,是复合谓语不可或缺的部分。【情境探究】观察上面对话,完成下列题目:1.对话中使用的情态动词是:_。2.完成句子(1)_ there before it rains.我们最好下雨前去那儿。(2)_ him.你最好不要打扰他。had betterWed better goYoud better not disturb【要义详析】一、基本特征1.情态动词有一定的词义,不能单独作谓语,需和实义动词或系动词一起作谓语。*She can speak Engl

2、ish though she is six.虽然她才6岁,但她会说英语。2.情态动词一般无人称和数的变化,个别情态动词有现在时和过去时两种时态变化。*They must be in the classroom.他们一定在教室里。3.构成否定句时,not放在其后面。*The young man cant carry the big stone.这个年轻人搬不动那块大石头。4.情态动词后接动词原形。*Jogging can be harmful to the health.慢跑可能会对身体健康有害。二、be able to 的用法1.be able to后跟动词原形,表示具体的能力,与can的用法

3、相近。*I am not able to answer your question.我回答不了你的问题。2.be able to与can/could的区别。(1)be able to有更多的时态形式,can只有一般现在时和一般过去时。*Will you be able to come tomorrow?你明天能来吗?*Im sorry I havent been able to answer your letter in time.很抱歉我没能及时给你回信。(2)was/were able to do sth.表示过去成功做成了某事,相当于succeeded in doing sth.。cou

4、ld仅表示客观上有某种能力,不说明实施该能力后的结果。*The maths problem was hard,but I was able to work it out.这道数学题目虽难,但是我做出来了。*By the time she was eight,she could read Greek and Latin.她八岁就会读希腊文和拉丁文了。(3)be able to可用在may/might,want之后。*I want her to be able to use a computer.我希望她能使用电脑。【即学活用】选词填空(can/be able to)(1)If you have

5、a good sleep,you will _work out this problem.(2)When I was young,I _ climb any trees in the woods.(3)Who _ answer this question?(4)He might _fix your car.be able tocouldcanbe able to三、have to 的用法1.have to意为“不得不,必须”,后跟动词原形。*I have to be off now.My mum is waiting for me.我得走了。妈妈在等我。2.have to与must的区别。(1

6、)must强调说话者的主观意愿;have to强调客观上的必要性。*The last bus left,and he had to walk home.最后一班公共汽车走了,他只好步行回家。*I must finish the project by Friday.周五前我必须完成这个项目。(2)mustnt 不许,不可以,表示禁止;not have to不必。*You dont have to do the work right now.你现在不必做这项工作。*You mustnt play football in the street.你千万不要在大街上踢足球。【即学活用】(1)Id als

7、o like to know how much I _for the course.我还想了解一下学这门课程得付多少钱。(2)The new law states that people _after drinking alcohol.新法律禁止人们酒后驾车。have to paymustnt drive(3)We _hurry,for theres plenty of time.我们不必着急,因为时间很充裕。(4)We _home by six.我们必须在6点以前到家。dont have tomust be四、had better的用法had better后跟动词原形,表示“最好”,其否定形

8、式在had better 后加not。*We had better get there before it gets dark.我们最好天黑前到达那里。*Youd better not talk so loudly.你最好不要这么大声说话。【即学活用】(1)You _there by plane.你最好不要乘飞机去那里。(2)You _watch out.你最好小心谨慎。had better not gohad better五、dare与needneed和dare既可用作情态动词,也可用作实义动词。用作情态动词时,主要用于否定句和疑问句中;用作实义动词时,可用于各种时态。(1)用作情态动词*A

9、re you coming with me?I cant,Alice.I darent.你要和我一起去吗?不行,爱丽丝。我不敢。*Its quite warm here;we neednt turn the heating on yet.这里很温暖,我们还不必开暖气。(2)用作实义动词*You dont need to do it yourself.你不必亲自做这件事。*Most people hate Harry but they dont dareto say so.大多数人对哈利敢怒不敢言。【即学活用】语法填空(1)Dare you _(tell)her the news?(2)I darent _(go)out alone at night.(3)He dares _(say)whatever he wants to say.(4)You neednt _(come)if you are busy.(5)I need _(get)some sleep.tellgoto saycometo get