Possibility with “might / may”

might / may + base verb — the same for every subject, no -s, no to. Negative: might not / may not (may not is almost never contracted; mightn't is found in British English but is not common).

• In progress: might / may be + -ing.
• Past: might / may have + V3 — see the lesson “Modal perfect”.
• Asking about possibility: usually Do you think…? or Could…?: Do you think it'll rain? Could she be at home? May is not used for questions like this.

💡Don't confuse may be (two words, a verb: She may be late) with maybe (one word, meaning “perhaps”, usually at the start: Maybe she'll be late). Not “She maybe late”.

1. Something may be true now — a guess, not a certainty

• Lan isn't answering. She might be in a meeting.

• This may be the wrong address — let me check.

2. Something may happen in the future

• Take a jacket. It might get cold tonight.

• We might go to Da Lat next month — we haven't decided yet.

• I may not have time to cook, so let's order food.

3. Something may be happening now: might / may be + -ing

• Don't call now — the baby might be sleeping.

• I'm not sure where Tuan is. He may be playing football.

4. Something may have happened: might / may have + V3

• I can't find my keys. I might have left them at work.

• She may not have seen your message.

For possibility, may, might and could in positive sentences mean almost the same. May is more formal and common in writing and announcements; might is the most common in speech; some people feel might is a little less sure than may.

• It could rain later, so take an umbrella.

• The flight may be delayed because of the storm.

  announcement style

• might well / may well / could well = quite likely: Prices might well go up again next year.
• Don't put two modals together: use might be able to, not “might can”: I might be able to help you tomorrow.
• May I…? asks for permission, not possibility — see the lesson “Requests, offers and permission”.

In positive sentences could ≈ might, but in negative sentences they are very different. might not / may not = possibly not (still not sure). can't / couldn't = definitely not possible — see the lesson “Deduction: must / can't”.

• Hoa might not be at home. She sometimes works late.

• Hoa can't be at home. I've just seen her at the gym.

💡Watch the word order of the idea: “possibly not” = might not (not sure), but “not possible” = can't (sure). Don't use can't when you only mean “maybe not”.

• ✗She maybe come to the party.

  ✓She may come to the party. / Maybe she'll come to the party.

  Maybe is an adverb; it can't replace the verb.

• ✗It might rains later.

  ✓It might rain later.

  After might, use the base verb — no -s.

• ✗We might to visit Hue.

  ✓We might visit Hue.

  No to after might / may.

• ✗I might can help you.

  ✓I might be able to help you.

  Two modals can't go together.

• ✗The shop might closed today.

  ✓The shop might be closed today.

  Closed is an adjective, so it needs be.

• ✗Lan might be study now.

  ✓Lan might be studying now.

  For something in progress: might be + -ing.