Might comes first in the verb phrase (after the subject and before another verb):
She might sell her house.
This might be true.
Not: That might can be true. or That can might be true.
The negative form of might is might not or mightn’t. We don’t use don’t/doesn’t/didn’t with might:
There might not be anyone in the house. (or There mightn’t be …)
Not: There doesn’t might be anyone in the house.
The subject and might change position to form questions.
We don’t use do/does/did:
Might this be the key?
Not: Does this might be the key?
Mightn’t this be the key?
Not: Doesn’t might this be the key?
We can use might and mightn’t in question tags, but they’re not very common:
That might not be a bad idea, might it?
That plant might do better by the window, mightn’t it?
We use might most often to refer to weak possibility:
I might go to Japan for a month to study Japanese.
The dog might bark when we pass by the gate.
They might not like very hot food.
We use might to refer to permission. It is very formal and is not used very often:
Might I ask your name?
Might I interrupt you for a moment?
The reply to these will not contain might:
A:Might I ask your address?
B:Yes. It’s 41 Ross Avenue.
A:Might I ask you a question?
B:Yes. Of course.
Not: Yes. You might.
We can use might to give advice or make a suggestion sound more polite or less direct, especially when used together with like, prefer or want:
[A waiter politely suggesting a dessert to a customer.]
You might like to try one of our wonderful desserts.
We often use might have + -ed form to express disapproval or criticism:
You might have told me you weren’t coming home for dinner. (you didn’t tell me)
You might have tidied your room.
We use might as the past form of may in indirect reports:
‘That may not be true’, she said.
She said that it might not be true.
We don’t use might for ability; we use can or could:
Although you can visit these places, if you are tired, you’re welcome to stay in the hotel.
Not: Although you might visit these places …
I could hear the noise of an engine.
Not: I might hear the noise of an engine.