8. Present and future
May and might + infinitive are used to express present or future possibility. May expresses a greater
degree of certainty:
You should ask him. He may/might know Susan's telephone number. (Perhaps he knows her number.)
I may/might see you later. (Perhaps I will see you later.)
You should introduce yourself; he may/might not remember you. (Perhaps she doesn't/won't remember
you.)
May and might are usually not used to introduce a question. Instead, we can use Do you think? or be
likely to/that:
Do you think he may/might know Susan's telephone number?
Are you likely to get here before 8?
Is it likely that you will get here before 8?
Could can be used instead of may and might with the verb be:
You could be right.
They could still be waiting for us.
9. The negative form couldn't is often used with comparative adjectives:
The food is delicious, and the staff couldn't be more polite. (they are very polite)
Except for this use, couldn't expresses negative deduction, not possibility:
It's only 10 o'clock. He couldn't be at home. (He is usually at work at this time of the day.)
Can may express general possibility:
Winters in Minnesota can be really cold.
Past
May, might and could + perfect infinitive express uncertainty with reference to past actions:
We haven't heard from him for ten years. He may/might/could have died. (Perhaps he has died, but we
don't know.)
But when we want to say that something was possible but did not happen, we use might or could:
He was very careless when crossing the road. He might/could have died. (He didn't die.)
I could have caught the bus if I had hurried. (I didn't hurry, so I didn't catch the bus.)
10. NOTE: Positive Negative
I may I must not
MAY – BE ALLOWED TO
I may go out. = I am allowed to go out.
Present tense - Past tense
I am allowed to go. - I was allowed to go.
He, she, it is allowed to go. - He, she, it was allowed to go.
You, we, they are allowed to go. - You, we, they were allowed to go.
Present perfect - Will – future
I have been allowed to go. - I will be allowed to go.
He, she, it has been allowed to go. - He, she, it will be allowed to go.
You, we, they have been allowed to go. - You, we, they will be allowed to go.
11. Very sure
People will definitely work from home more in the future.
Robots definitely won't replace all human jobs.
Sure
Donna will really enjoy this film.
You won't regret it.
Look at these examples to see how we can express different degrees of certainty about
the future.
I'll definitely be at the meeting, don't worry.
She's likely to say yes if you ask nicely.
It probably won't rain later according to the weather forecast.
Almost sure
We'll probably finish the project by tomorrow.
He probably won't have enough time.
Not sure
I might go to the party, but I'm not sure yet.
He hasn't studied much, so he might not pass the exam.
When you are not sure, we can also use may, could and may not. However, we don't usually use could not to talk about the future.
