Can

(Can, could, will be able to do)

1. Ability/capability

+ - ? Can=be able

Can you open this door? – No, it’s closed.

2. Possibility due to circumstances

+ - ?

I can buy a cat – я могу купить кота

I could buy a cat – я могла купить кота (Past time context)

Unreal action (if2)

I could buy a cat if I weren’t allergic.

(could + inf – unreal action)

IF 3

I could have bought a tablet if I had had money last year.

___________________

I could buy a cat – я мог купить кошку

I was able to buy a cat – я смог

I managed to buy a dog – я смог

I wasn't able / I didn't manage / I failed to do – я не смог

I succeeded in doing smth – я смог

I succeeded in buying a cat

I didn’t succeed in buying a cat

3. Permission

+ - ? Can = could (could is more polite)

You can take my notebook.

You can’t take my notebook.

Can I take your notebook?

Could is usually used in reported speech.

4. Doubt/uncertainty (НЕУЖЕЛИ) Only ?

Can = could (could – more uncertain)

Can he be at home? – simple inf.

Can he be sleeping? – continuous inf.

Can he have fallen ill? – perf. inf.

Can he have been ill for 3 days? – perf. inf.

Can he have been sleeping for 3 days? – perf. cont. inf.

5. Improbability НЕ МОЖЕТ БЫТЬ Only -

Can = could (could – more improbability)

He can’t be at home. He can’t have died. He can’t be walking with her. He can’t have been sleeping for 3 days.

6. Puzzlement. Only in special questions.

Can = could

Where can he be? Why can he be sleeping now? Why can he have gone? Why can he have been sleeping for 3 hours?

Set-phrases.

1. Can’t/ couldn’t help doing smth – не могу не

She couldn't help singing.

2. Can't but – ничего не оставалось, как…

He couldn't but kill his friend.

3. I cannot possibly do smth – просто не могу…

I cannot possibly go there.

MAY

1. Supposition implying uncertainty МОЖЕТ БЫТЬ

+ - ? May = might (might – more uncetrain)

He may/might be at home

He may/might be working now

He may/might have fallen ill

He may/might have been working for 10 hours

To refer an action in the future we use may + inf

2. Possibility due to circumstances

+ may = can

I may buy a tablet.

I might buy a tablet if I had money now

I might have bought a tablet if I had had money last year

! Might + perfect inf. – the action which wasn’t carried out - ЧУТЬ НЕ

She might have dropped a cup

3. Permission

+ - ? may=can/ might = could

May I take your notebook? – Yes, you may. – No, you may not.

In reported speech:

He said that I might take his car

4. Reproach

+ only might

You might clean your room, it’s messy

You might have cleaned your room yesterday

Simpe inf – present action

Perfect inf – past action Might = could

Set-phrases:

• I may as well stay at home – я, пожалуй, останусь дома

• It might have been worse – могло быть и хуже

• He might have been a sailor – его можно было принять за моряка

• If I may say so – так сказать… (вводная фраза)

MUST

1. Supposition implying strong probability

ВЕРОЯТНО, ДОЛЖНО БЫТЬ

He must be ill

He must be sleeping

He must have fallen ill/ He must have been ill for 3 days

He must have been sleeping for 3 hours

! Must isn’t used in reference to the future

Probably is used instead.

He will probably be back tomorrow.

! Must isn’t used in negative sentences

Express the meaning by using negative words.

He must have failed in life

They must have never been to London Etc.