Did is the simple past form of do. We use it when we talk about actions that happened before now. It shows something was done or happened in the past.
She did her homework last night.
I did the dishes after dinner.
Did helps make past tense questions and negative sentences. It goes before the main verb but does not change the main verb form.
Did you see the movie?
He did not go to school today.
Did can be used to stress that an action was really done. It adds strong emotion or proof showing the action is true, often in positive sentences.
I did finish my work on time!
She did call you yesterday.
In informal or slang speech, did can mean to have sexual intercourse. This usage is common in casual conversations but considered informal or rude in some places.
They did last night after the party.
Did you do her at the concert?
In some dialects of English, did is a noun meaning a small part or piece, often of food. This use is old or regional and not common in standard English.
Give me just a did of cheese.
He took a did of bread from the table.
In informal speech, 'the did' means an event or situation that was interesting or important. It is a casual way to refer to something that happened.
The did at the party was unexpected.
Everyone talked about the did all day.
