Using the past tense after did instead of the infinitive without to.
(a) To ask questions:
Don’t say: Did you went to school yesterday?
ü Say: Did you go to school yesterday?
(b) To make negatives:
Don’t say: I did not went to school yesterday.
ü Say: I did not go to school yesterday.
Use the present infinitive without to, not the past tense after the auxiliary did.
Note: the answer to a question beginning with did is always in the past tense: Did you see the picture? – Yes, I saw the picture; or Yes, I did.