CAN - COULD

Modal verbs CAN and COULD

Modal verb CAN

1. Use CAN to express ability

Can means to be physically or mental able to do something OR to know how to do something.

Dogs can bark. Cats can't bark.

She can speak English. I cannot find a decision.

2. Use CAN to express possibility (in general)

This refers to a theoretical meaning.

Smoking can cause a cancer.

3. Use CAN to offer to do something for others

Can is used when you offer to help someone or to do something for them.

I can take you there if you like.

Can I carry your luggage for you?

4. Use CAN to ask for or give permission / To request something

Can is used to ask for / request permission or to give permission.

Note: Can't is used to refuse permission.

You can use my pencil; I don't need it right now.

Can I sit in that chair please?

Joan, you can help your brother set the table.

Can I ask you a question?

You can't go to the cinema before you have finished your homework.

We can't leave the room till the exam has finished.

5. Use Can't when something is forbidden or not allowed

We cannot park the car next to a crosswalk.

You can't smoke in the hospital.

You cannot drive a car without a driver’s license.

6. Use Can't when you are sure that something isn't true, or something is surprising

The cake can't be ready yet! It's been in the oven for 5 minutes!

Modal verb COULD

COULD is used as the past tense of CAN or when we want to be more polite in the present

1. Use COULD to express ability in the past

I could swim fast when I was younger, but now I can’t.

My sister could read when she was only 4 years old.

When we were children, we could ride a bicycle all day long.

2.  Use COULD when you politely ask for permission or request in the present

Could I please take your car?

Could you pass me the salt, please?

Could you call me later, I can’t speak right now?

  

3. Use COULD for general permission in the past

In high school we couldn’t leave the classroom without the teacher’s permission.

4. Use COULD for a polite suggestion in the present

We could go to the beach for a walk if you want.

We could order a pizza for dinner.

5.Use COULDN’T to say that something isn’t true or real

He couldn’t pass the exam, because he didn’t study at all.

6. Use COULD + have + past participle to express a possibility in the past (when something was possible, but didn’t happen)

Why did you drive a car without a driver’s license? You could have caused a crash!

7. Use COULD + have + past participle to express unrealized past ability

This is used to say that someone was able to do something, but they did not try to do it. Sometimes this is a form of criticism.

She could have been a doctor if she didn’t give up in the college.

She could have passed the exam if she studied harder.

8. Use COULD in conditionals

Could = would be able to

I could write the email if you told me it’s urgent.

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Модални глаголи 😃 Modal verbs:

CAN - COULD
MAY - MIGHT
WILL
WOULD
SHALL
SHOULD
MUST
DARE
OUGHT TO
HAD BETTER
NEED
BE ABLE TO