When you're not sure about something now or in the future, use might, may or could + a base verb. They all mean "maybe" or "it's possible." Might is the most common in American conversation, and may sounds a little more formal.
The pattern
It might rain later.
Maybe the store is closed.
Do you think it will snow?
01Might, may and could + base verb
Put might, may or could before the base verb. Don't add -s and don't add to: she might come, not she might comes. For something that is possibly happening right now, use might be + -ing: He might be driving.
In positive sentences the three mean almost the same thing. Could often points to a risk or an option: The price could go up.
- Our landlord might sell the building.
- I may need your help on Friday.
- Be careful, the stairs could be slippery.
- She might be sleeping, so text first.
| Sure | Not sure |
|---|---|
| She's at work. | She might be at work. |
| It will rain. | It may rain. |
| The game is sold out. | The game could be sold out. |
02Might not or can't?
For a negative guess, use might not or may not: He might not come (maybe he won't). Don't use could not for this. Can't and couldn't mean you are sure something is impossible: That can't be Tom. He's in Miami this week.
In American English, don't contract might not to mightn't. Just say might not.
- I might not finish the report today.
- We may not get a table without a reservation.
- That can't be the right bus. It's going the wrong way.
03Maybe or may be?
Maybe (one word) is an adverb. It usually starts the sentence, and a full sentence follows: Maybe she's busy. May be (two words) is the verb: She may be busy. Quick test: if you can replace it with might be, write two words.
- Maybe we should take a cab.
- The museum may be free on Sundays.
- Maybe I'll see you at the game.
04Asking about possibility
Americans rarely start a question with might or may, and May I...? is for permission, not possibility. To ask if something is possible, use Do you think...?, Is it possible that...? or Could it be...?
- Do you think they'll hire her?
- Is it possible that the meeting will run late?
- Could it be the battery?
05Common mistakes
It might rains tomorrow.
It might rain tomorrow.
After might, may and could, use the base verb with no -s.
She might to call later.
She might call later.
Don't put to after might, may or could.
May be the store is closed.
Maybe the store is closed.
At the start of a sentence, use maybe as one word.
I couldn't come tonight. I'm not sure yet.
I might not come tonight. I'm not sure yet.
Couldn't means impossible or past. For maybe not, use might not.