eg. I can’t speak English.
She could read when she was three years old.
Asking or Giving Permission: can/ may/ could
eg.You can smoke in the garden.
Could I go to the toilet, please?
When I was a child I could only have dessert if I’d eaten my dinner.
Obligation: must/ have to
eg. I have to go to a meeting tomorrow.
I must go to the dentist about my toothache.
Giving Advice: should/ ought to
eg. You should go to the doctor if you don’t feel well tomorrow.
She ought to change jobs.
Repeated/Typical Behaviour: will/ would
eg. I’ll finish work and immediately go to the gym.
Before he retired, he would always get the bus to work.
Refusal: won’t/ wouldn’t
eg. She won’t let me borrow the car.
He wouldn’t give me any money.
Criticising Past Behaviour: ought to have/should have + past participle
eg. She shouldn’t have carried so much cash in her bag.
They ought to have caught the robber by now.
eg. You can’t speak loudly in a library.
You can’t park here at rush hours during the week.
be allowed to : to say we have permission to do something
eg. We were allowed to stay up late in the summer holidays.
manage to: to say we succeeded in doing something, often after some difficulty
eg. After being lost for some hours, we managed to find our way out of the forest.
be able to: ability or possibility
eg. I might be able to finish this report on time.
was able to: to have the ability to do something and do it.
eg. I was able to leave work early today.
need/ needn’t/ don’t need to: to talk about things that are necessary (or not) for us to do
eg. I need to go to the bank.
I don’t need to/needn’t go to the bank.
didn’t need to/ needn’t have done: to talk about something that was not necessary to do in the past
NB: these two structures have a difference in meaning
eg. I didn’t need to get a visa to go to Thailand. (so I didn’t)
I needn’t have got a visa to go to Thailand. (but I did)
Levels of Certainty
When we think something is definite: will, won’t, can’t, must, would(n’t)
eg. He’s on holiday so he’ll be relaxing on a beach somewhere.
Due to his financial situation, it won’t be easy for him to go to university.
He can’t be home. All the lights are out.
He must be thrilled that his business is thriving.
I wouldn’t have left home if I’d realised how much it costs.
When we think something is probable: should
eg.The queue is moving quickly, so it shouldn’t be long before we get to the front.
When we think something is possible: may, might, could
eg. I may have been good enough to have played professionally.
He might be downstairs in the study.
He could be working in the garden.
When modal verbs refer to the present we use: modal + infinitive or modal + be + verb + ing
eg. She must do a lot of travelling.
I’m sure he’ll be relaxing on a beach somewhere.
When modal verbs refer to the future we use: modal + infinitive
eg. It won’t be easy for him to go to university.
When modal verbs refer to the past we use: modal + have + past participle
eg. He must have been at high school when I was at primary school.
She might have been to Africa. She’s been to a lot of places!