Grammar

Find the sentences containing modal

verbs in the reading passage.

•Then usually by lunchtime they would

all be sold.•What could have happened?•Nothing could be better…”•Something terrible must have

happened if …

He could not believe his eyes.Perhaps he should go to the library

and find out.He had better do some research!Even though her customers might get

thin after eating Yong Hui’s food…They would become tired very quickly.

Modal verbs

a. should, ought to 都可表示“应该”。 ought to 用于表示按道理应当，常指客观的义务或责任，大多数情况下可用 should 代替，但比 should 语气重。

I should help her because she is in

trouble.

You ought to take care of the baby.

b. 表示劝告、建议或命令时， should 和ought to 可通用，但在疑问句中常用should 。 ought to 的否定式为oughtn’t to 或 ought not to 。

You should / ought to go to class right

away.

Should I open the window?

What should we do next?

c. should, ought to 都可表示推测。

He ought to / should be home by now.

This is where the oil ought to / should

be.

should 和 ought to 后面跟动词不定式的完成式 , 其肯定句表示“过去应该做而未做” , 其否定句则表示 “过去不该做但做了”。You should/ought to have made the decision a week ago.I shouldn’t have made such a foolish mistake. 多数情况下， ought to 可与 should 互换使用。ought to 的反意疑问句用 shouldn’t 替代。

注意

You ought to have helped him

with his English, ________?

A. won’t you

B. ought not you

C. shouldn’t you

D. wouldn’t you

2. must 和 have to

　 must 的用法 1) 表示主观的义务和必要 ,  主要用于

肯定句和疑问句 ,  意思为 “必须……，得……，要……”；由 must 引起的疑问句，肯定回答要用 must 或 have to,  否定回答要用 needn’t 或 don’t have to,  意思是“不必” ；

must 的否定形式 mustn’t 表示禁止，意思是“不能，不许”。如：

— Must I finish the task right now? 

　 我现在必须完成这个工作吗？

—Yes, you must. / Yes, you have to. 

是的。 (—No, you needn’t. / No, you don’t

have to. 不，不必。 )

You mustn’t come here without

permission.

未经允许，你不能来这儿。　　

have to  的用法

1) must 表示一种主观的需要，而have to 表示一种客观的需要，意思是“不得不”。 如：

I have to attend an important

meeting this afternoon.

今天下午我不得不参加一个重要的会议。

Mother is out, so I have to look after the shop.

　 妈妈不在家，因此我不得不照看商店。

2) have to  的否定形式是 don’t have to, 相当于 needn’t 。如：

They don’t have to buy a computer at present. 　 他们目前没有必要买电脑。

【考例】 The boss has given everyone a

special holiday, so we ____ go to work

tomorrow. ( 上海 2007 春 )

A. can’t B. mustn’t

C. needn’t D. shouldn’t

【点拨】考查情态动词。根据题意 , 可知这里表示“没有必要” , 故只能选 C

项。

【考例】─ What do you think we can do for our aged parents?─You ____ do anything except to be with them and be yourself. ( 重庆 2007)A. don’t have to B. oughtn’t toC. mustn’t D. can’t 【点拨】根据题意“除了和他们呆在一起做你自己外 , 没有必要做任何事情。”可知这里选择 don’t have to 表示“不必”。故选 A 项。

3. must 和 need

a. need 作情态动词时 , 只能用于疑问句和否定句。构成否定句和疑问句时不借助于助动词 do 。

—Need I finish the work today?

—Yes, you must. / No, you needn’t.

b. must 的肯定形式表示“必须”，否定式 表示“禁止、严禁”。 You must come here.

You mustn’t take the book away from

the library.

用下列图片造句。

做适当的运动 You should do some sports.

慢慢地进食，并有助消化。 You ought to eat slowly and it’s good for digestion.

You should help to set the dinner table.

You should keep your room clean.

We must listen to the teacher carefully.

We mustn’t eat in class.

You ought to hand in the homework on time.

You shouldn’t be late for school.

We should ask question actively.

We shouldn’t make noise in class.

Make sentences

1. 你每天最少要练习一小时口语。 You must practise speaking English

at least an hour a day ． 2. 我每天不得不练习一小时口语！ I have to practise speaking English

an hour a day ！

3. 你应该每天练习不止一小时。 You ought to ／ should practice

English for more than an hour ． 4. 你应该读一下这个。它写得很好。 You ought to ／ should read this ． It’s very good ． 5. 你必须读这个。写得精彩极了！ You must read this ． It's marvelous ！

Please choose a proper phrase and

according to the situations complete

the sentences by using should (not) or

ought (not) to.

1. Lisa needs a change. She

_______________________________.

2. My salary is very low. You

______________________.

should/ought to take a few days off

should look for a new job

3. Nick always has difficulty getting

up. He _______________________

____________.

4. What a beautiful view! You

__________________.

5. Billy’s room isn’t very interesting.

He ___________________________

___________.

ought not to /shouldn’t go

to bed so late

should take a photo

shouldn’t/ ought not to use her

car so much

Choose suitable modal verbs below to complete the following dialogues.

ought/oughtn’t to should/ shouldn’t mustn’t needn’t (don’t) have to will can/ can’t

1 Sam: How can I grow thinner, Mum?Mum: Well, you _______ eat food with plenty of fibre that helps you digest better. And you _____ stop drinking cola or eating sweet food.

have to

should

Sam: Does it mean I _________ eat my

favourite fried chicken any more?

Mum: Not exactly, if you love fried

chicken, you ______ give it up.

Just eat it less often. You

______________________________

worry too much: a little fried

chicken ____ do you good!

shouldn’t

needn’t

don’t have to/ needn’t/ shouldn’t

will

2 Doctor: You are sick because you’ve eaten poisonous mushrooms. Where did you get them?Lucy: I picked them in the forest. I know we _______ eat fresh vegetables.Doctor: Oh, but you _______ eat them until you’re sure they are not poisonous.Lucy: Thank you, doctor. I’ll be more careful next time.

have tomustn’t

3 Charles: I wish I could see things

clearly in the dark.

Tom: Eating carrots _______ help

you see better. You _______ eat

some every day.

ought to

should

1. _______ to discuss something with

someone so that you can make a

decision together

2. _______ to change food that you have

just eaten into substances that your

body can use

练习坊

I. 根据下列英文解释写出所缺的单词。

consult

digest

3. ______ a long pointed orange

vegetable that grows under the

ground

4. __________ containing poison or

producing poison

carrot

poisonous

1. For a long time, I’ve built my

business with people who are

________ ( 精力旺盛的 ), creative,

and happy about their work.

2. This rich food doesn’t _____ ( 消化 ) easily.

energetic

digest

根据下列各句句意及所给单词的汉语提示 , 写出各单词的正确形式。

3. The dish of boiled beef and _____

( 胡萝卜 ) tastes good.

4. An increasing number of people

are _________ ( 请教 ) their

accountants about the tax laws.

5. This medicine is _________ ( 有毒 ) if taken in large quantities.

carrot

consulting

poisonous

must; oughtn’t to; don’t have to; couldn’t;mustn’t; needn’t; can’t; have to

II. 用所给的情态动词填空。

1. You _______________________ go on

working because you look so tired now.

2. The weather turned out to be fine

yesterday. I _______ have had the

trouble to carry my umbrella with me.

oughtn’t to / don’t have to

needn’t

must; oughtn’t to; don’t have to; couldn’t;mustn’t; needn’t; can’t; have to

3. If you earn more than ￡ 5,000, you

_______ pay tax.

4. You _______ play now!You shall finish

your homework first!

5. I know things are hard with you, but

you _____________ try to get over the

difficulties.

have to

mustn’t

must / have to

must; oughtn’t to; don’t have to; couldn’t;mustn’t; needn’t; can’t; have to

6. I didn’t see her at the meeting this

morning; she _____________ have

spoken at the meeting.

couldn’t / can’t

1. I thought you __ like something to read,

so I have brought you some books.

A. may B. might C. would D. must

2. Where is my pen? I ____ it.

A. might lose B. would have lost

C. should have lost D. must have lost

高考链接

3. I didn’t hear the phone. I __ asleep.

A. must be B. must have been

C. should be D. should have been

4. --Is John coming by train? --He should, but he __ not. He likes

driving his car. (2002 高考题） A. must B. can C. need D. may5. It has been announced that

candidates ( 候选人 ) ____ remain in their seats until all the papers have been collected. (2002 上海高考题）

A. can B. will C. may D. shall

6. --I heard they went skiing in the

mountains last winter.

--It ____ true because there was little

snow there. (2002 北京高考题 )

A. may not be B. won’t be

C. couldn’t be D. mustn’t be

7. ---There were already five people in the

car, but they managed to take me as well.

---It ___ a comfortable journey.

A. can’t be B. shouldn’t be

C. mustn’t have been D. couldn’t have been

8. It’s nearly seven o’clock . Jack __ be here

at any moment.

A. must B. need C. should D. could

Homework

1. Preview the reading (2) and

reading task on Page 52. See how

the story ended.

2. Find some information about

healthy eating on the Internet.