Unit 29. May and might (1)

You are looking for Bo. Nobody is sure where he is but you get some suggestions.
"Where's Bob?"

A : He may be in his office ( = perhaps he is in his office )
B : He might be having lunch ( = perhaps he is having lunch )
C : Ask Ann. She might know. ( = perhaps she knows )

We use may or might to say that something is a possibility. Usually you can use may or might, so you can say?

• It may be true. or It might be true. ( = perhaps it is true)
• She might know. or She may know.

For the past we use may have (done) or might have (done)

• A : I wonder why Kay didn't answer the phone.
  B : She may have been asleep. ( = perhaps she was asleep )
• A : I can't find my bag anywhere.
  B : You might have left it in the shop. ( = perhaps you left it in the shop )
• A : I was surprised that Sarah wan't at the meeting.
  B : She might not have known about it. ( = perhaps she didn't know )
• A : I wonder why Colin was in such a bad mood yesterday.
  B : He may not have been feeling well. ( = perhaps he wasn't feeling well )

Sometimes could has a similar meaning to may and might.

• The phone's ringing. It could be Tim. ( = it may/might be Tim )
• You could have left your bag in the shop. ( = you may/might have left it... )

Bet couldn't (negative) is different from may not and might not.

• She was too far away, so she couldn't have seen you.
  ( = it is not possible that she saw you )
• A : I wonder why she didn't say hello.
  B : She might not have seen you. ( = perhaps she didn't see you; perhaps she did)