Irregular Verbs

AFFIRMATIVE (simple past)
I sat on a chair
You sat on a chair
He sat on a chair
She sat on a chair
It sat on a chair
We sat on a chair
You sat on a chair
They sat on a chair

NEGATIVE (infinitive)
I didn't sit on a chair
You didn't sit on a chair
He didn't sit on a chair
She didn't sit on a chair
It didn't sit on a chair
We didn't sit on a chair
You didn't sit on a chair
They didn't sit on a chair

INTERROGATIVE (infinitive)
Did I sit on a chair
Did you sit on a chair
Did he sit on a chair
Did she sit on a chair
Did it sit on a chair
Did we sit on a chair
Did you sit on a chair
Did they sit on a chair