Грамматика

Must and can’t

A. Study this example:

  • A: My house is very near the motorway.
  • B: It must be very noisy.

 

We use must to say that we feel sure something is true:

 

  • You’ve been travelling all day. You must be tired. (Travelling is tiring and you’ve been travelling all day, so you must be tired.)
  • ‘Jim is a hard worker.’ ‘Jim? A hard worker? You must be joking. He’s very lazy.’
  • Carol must get very bored in her job. She does the same thing every day.

 

We use can’t to say that we feel sure something is not possible:

 

  • You’ve just had lunch. You can’t be hungry already. (People are not normally hungry just after eating a meal. You’ve just eaten, so you can’t be hungry.)
  • Brian said he would definitely be here before 9.30. It’s 10 o’clock now and he’s never late. He can’t be coming.
  • They haven’t lived here for very long. They can’t know many people.

 

Study the structure:

 

I/you/he (etc.) must
can’t
be (tired / hungry / at work etc.)
be (doing / coming / joking etc.)
do / go / know / have etc.

 

B. For the past we use must have (done) and can’t have (done).

Study this example:

George is outside his friends’ house. He has rung the doorbell three times but nobody has answered.

They must have gone out. (otherwise they would have answered)

 

  • The phone rang but I didn’t hear it. I must have been asleep.
  • I’ve lost one of my gloves. I must have dropped it somewhere.
  • Jane walked past me without speaking. She can’t have seen me.
  • Tom walked straight into a wall. He can’t have been looking where he was going.

 

Study the structure:

 

I/you/he (etc.) must
can’t
have been (asleep / at work etc.)
been (doing / working etc.)
done / gone / known / had

 

Couldn’t have… is possible instead of can’t have:

 

  • She couldn’t have seen me.
  • Tom couldn’t have been looking where he was going.

EXERCISES

 

1 Put in must or can’t.

  1. You’ve been travelling all day. You   must be very tired.
  2. That restaurant________________ be very good. It’s always full of people.
  3. That restaurant________________ be very good. It’s always empty.
  4. You’re going on holiday next week. You ________________ be looking forward to it.
  5. It rained every day during their holiday, so they ______________ have had a very nice time.
  6. Congratulations on passing your exam. You ________________ be very pleased.
  7. You got here very quickly. You ________________ have walked very fast.
  8. Bill and Sue go away on holiday very often, so they ________________ be short of money.

 

2 Complete the sentences with a verb in the correct form.

  1. I’ve lost one of my gloves. I must have  dropped it somewhere.
  2. They haven’t lived here for long. They can’t _know_ many people.
  3. Ted isn’t at work today. He must___________________ ill.
  4. Ted wasn’t at work last week. He must___________________ ill.
  5. (The doorbell rings) I wonder who that is. It can’t________________ Mary. She’s still at work at this time.
  6. Carol knows a lot about films. She must___________________ to the cinema a lot.
  7. Look. Jack is putting on his hat and coat. He must___________________ out.
  8. I left my bike outside the house last night and this morning it isn’t there any more. Somebody must _______________ it.
  9. 9 Ann was in a very difficult situation. It can’t___________________ easy for her.
  10. 10 There is a man walking behind us. He has been walking behind us for the last 20 minutes. He must ___________________ us.

 

3 Read the situations and use the words in brackets to write sentences with must have and can’t have.

  1. The phone rang but I didn’t hear it. (I / asleep) I must have been asleep.
  2. Jane walked past me without speaking, (she / see / me) _She can’t have seen me_
  3. The jacket you bought is very good quality, (it / very expensive)_____________________________
  4. I haven’t seen the people next door for ages. (they / go away)______________________________
  5. I can’t find my umbrella. (I / leave / it in the restaurant last night)__________________________
  6. Don passed the exam without studying for it. (the exam / very difficult)______________________
  7. She knew everything about our plans, (she / listen / to our conversation)_____________________
  8. Fiona did the opposite of what I asked her to do. (she / understand / what I said)_______________ ______________________________________________________________________
  9. When I woke up this morning, the light was on. (I / forget / to turn it off)______________________
  10. The lights were red but the car didn’t stop. (the driver / see / the red light)____________________
  11. I was woken up in the middle of the night by the noise next door. (the neighbours / have / a party) _______________________________________________________________________________