1. Obligation (from the speaker’s point of view)

1. I must go there at once.

2. In order to graduate you must pass your exams.

2. Prohibition

1. And remember you must not ask for things.

2. You must not smoke here.

3. Emphatic advice

1. You must see the film. It’s very good.

2. You mustn’t cry.

Exercise 1.

You are students now and you have to get up early.

1. Say what you must do every morning.

2. Say what you must do every day being students of English.

3. Say what you mustn’t do being students.

Exercise 2.

Complete the following sentences using the modal verb must to express obligation.

1. If you want to know English well, you …

2. If your spelling is poor, you …

3. If I want to cross the street and there is a red light, I …

4. If you are unwell, you …

5. If she wants to get to the Institute in time, she …

6. If she makes a lot of grammar mistakes, she …

7. If the students want to know grammar, they …

8. If the boys want to win the game, they …

9. If his English is not good, he …

10. If you want to be healthy, you …

Exercise 3.

Give possible answers. Use the suggestions given as the explanation of the prohibition.

Example:

May I smoke here? (The children are here.) – No, you mustn’t.

1. May I open the window? (It’s very cold)

2. May she do the work later? (It’s very important to do it in time.)

3. May Kate play the piano? (Father is writing his report.)

4. May she switch off the light? (I’m going to work.)

5. May the pupils leave the room? (The lesson isn’t over yet.)

6. May I look some words up in the dictionary? (You are writing a test-paper.)

7. May I stay away from the classes? (You are not ill.)

8. May I wash the sweater? (It has to be dry-cleaned.)

9. May I cross the river here? (It’s rather deep.)

10. May we read the letter? (It’s personal.)

Exercise 4.

Make up short dialogues as shown, making use of the cue words.

Example:

Ann: Let’s go for a walk.

Jane: I can’t.

Ann: Why can’t you?

Jane: Because I must help my mother.

1. to the disco do homework

2. to the library write a lot of exercises

3. to the shop visit my granny

4. to the cinema learn the poem by heart

5. to the country translate the article

6. to the party do the flat

7. to the conference look after my sister

8. to the club read up for the exam

9. to the football match help my mother about the

house

4. Supposition

1. 1. She must be about twenty.

2. He must be taking good care of his health.

3. She must have come home by now.

4. It must have been raining since the very morning.

5. He must have been sleeping when I called him.

Exercise 1.

Make sentences around key-words with ‘must’ expressing supposition.

Example: read

She must be reading this book now.

She must have read this book already.

She must have been reading all the time.

look for

He must be looking for us now.

He must have looked for us everywhere.

He must have been looking for us when you saw him.

1. type

2. have breakfast

3. write

4. study

5. work

Exercise 2.

Refer the statement to the past by changing the form of the infinitive.

Example: She must know about it. (Должно быть, она знает об этом.)

She must have known about it. (Должно быть, она об этом знала.)

1. They must be playing in the school-yard.

2. You must know her very well.

3. She must be very fond of you.

4. This must be the dog’s owner.

5. She must be laughing at you.

6. They must be taking you quite seriously.

7. The situation must be rather grave.

8. They must be great friends.

9. Somebody must be trying to frighten you away.

10. They must be doing their lessons.

Exercise 3.

Refer the following sentences to the past. Make all the necessary changes.

1. She must be surprised to find you here.

2. You must be blind not to see what kind of person he is.

3. This news must distress her.

4. It must be unpleasant for her to see you.

5. There must be a good view from the top of the garden now.

6. ‘You really believe he is guilty.’ – ‘He must be.’

7. His knowledge of English must be slight now.

8. Everything must go smoothly.

9. She must expect you to go there at once.

10. It must be dull for you here.

11. You must be hungry and cold after your trip up to town.

12. There must be a slight error in your statement.

13. She must be in the house. There is light in her windows.

14. I’m afraid you must talk to both of us.

15. To have so kind-hearted, so affectionate a sister must be a comfort to him.

16. She must leave a message for me before she goes.

17. Look, we must make those arrangements about the furniture and so on.

Exercise 4.

Answer the questions expressing supposition. Use the words in brackets.

Example: Where is Mother? (in the kitchen) – She must be in the kitchen.

1. Who is this? (the new teacher)

2. What’s the time? (3 o’clock now)

3. What’s this? (a new text book)

4. I wonder how much such a dress may cost? (35 pounds)

5. Whose copy-book is this, I wonder? (Mike’s)

6. Where are my slippers? (in the bathroom)

7. Why does Lena miss her class? (catch a cold)

8. Why is the tap leaking? (spoil)

9. Why is he looking for the key? (lose it)

10. Where is your text-book? (leave it at home)

Exercise 5.

Answer the following questions, using ‘must’ to express supposition. Mind the tense form of the infinitive.

Example:

Why didn’t he come? (to be ill) – He must have been ill.

1. Why isn’t he here? (to delay)

2. What would you say he is, judging by his appearance? (to be a painter)

3. How old was he when he set out on his first expedition to the North? (thirty)

4. Why are they never seen together now? (to quarrel)

5. What’s all that knocking in the next room? (to fix a shelf to the wall)

6. Where is she? (to wait for us at the entrance to the Museum)

7. How did he manage to arrive so soon? (to come by plane)

8. What accounts for their delay? (the fog)

9. Why didn’t he join in the discussion of the problem? (to have no interest in the subject)

10. Why is the photograph so pale? (the film, the expose to light)

11. Why was he so impolite? (to be annoyed with smb. for disturbing him)

Exercise 6.

Paraphrase the sentences using ‘must’.

Example:

It’s probably a very complicated machine.

It must be a very complicated machine.

1. I feel sure there is something unpleasant in the man.

2. The town was probably founded about six hundred years ago.

3. You have probably heard the story before.

4. We feel sure she likes her new job.

5. He probably postponed his visit to the relatives.

6. Probably the tower on the cliff is a lighthouse.

7. I am sure you’ve seen the film.

8. I’m certain they have changed the programme. The singer is singing a new song.

9. She was obviously upset by something.

10. They probably have realized what they were losing.

11. No doubt, you are tired of my talking.

12. No doubt she read about it in the papers.

13. He is sure to be out at this time.

14. Of course she has changed her mind.

Exercise 7.

Paraphrase the following sentences, using ‘must’ + Infinitive to express supposition.

1. Probably they wanted to find a short cut through the forest.

2. They are certain to be looking for you.

3. Apparently she was trying to make up her mind about it.

4. No doubt they abandoned the car afterwards.

5. They are sure to have taken the wrong turning.

6. He is sure to be waiting for you at the office.

7. Probably they have taken the necessary steps.

8. It looks as if he were out of practice, that’s why he lost the game.

9. I see a crowd of people before the door. No doubt something has happened.

10. He has obviously been working at this Research Institute for a long time. Everybody seems to know him.

11. Evidently they were getting ready for another experiment. They wanted no strangers at the laboratory.

12. Obviously he was speaking from his own experience. He sounded very convincing.

13. Judging by the frosted windows the weather today is surely far from warm.

14. Evidently she was ashamed of her behavior.

Exercise 8.

Fill in the gaps with the correct form of the infinitive.

1. The roofs and streets are wet. It must (to rain).

2. The book must (to be) worth reading if he has read it twice.

3. The house must (to build) in the middle ages. The walls are very thick and the windows narrow.

4. We must (to take) the wrong turning. I don’t recognize the road.

5. Judging by the expression of his face, he must (to impress) by what he heard.

6. Something serious must (to delay) him. He should have been here at least an hour ago.

7. He must (to practice) a lot if he was able to show such good results.

8. You must (to guess) the answer by now.

9. She must (to be fed up) with his rough manner, that’s why she lost her temper.

10. She must (to be) very unobservant if she didn’t notice the change in him.

11. Judging by his story he must (to expose) to many dangers and (to risk) his life more than once.

12. She must (to get over) the shock by now.

Exercise 9.

Translate the following sentences using ‘must’.

1. Вы, должно быть, только что вернулись из деревни.

2. По всей вероятности он забыл, что раньше он придерживался другого мнения.

3. Я не думаю, чтобы он сердился на вас. Он, должно быть, был в плохом настроении.

4. Сейчас еще рано звонить ему. Вероятно, он еще спит.

5. Какой прекрасный телевизор. Должно быть, вы за него много заплатили.

6. Ты, должно быть, очень голоден. Ведь ты не ел с утра.

7. Я плохо себя чувствую. У меня, должно быть, температура.

8. Не случайно вас остановил милиционер. Вы, должно быть, превысили дозволенную скорость (лимит скорости).

9. Он, должно быть, давно болен. Он все время жаловался на плохое самочувствие.

10. Она, должно быть, задумалась и не заметила, как проехала свою остановку.