Affirmative: SUBJECT + [VERB + ed] or IRREGULAR VERB
- I played football yesterday. (regular verb)
- Leonardo da Vinci lived from 1452 to 1519. (regular verb)
- She bought some fruit last night. (irregular verb)
- They saw him in the park. (irregular verb)
Negative: SUBJECT + did not + [VERB]
- I did not wash the dishes.
- You did not play the piano.
- She didn’t sleep well last night.
- Sharon didn’t put the book on the table.
- did not = didn’t
- Did you have your breakfast? Yes, I did / No I didn’t.
- Did she work yesterday? Yes, she did / No, she didn't.
You can add a question word (what, where, when, etc.) before did to ask for more information.
- What did you do the last weekend? I studied Science.
- Where did she go? She went to the school.
- When did you play baseball? I played baseball last night.
- Why didn’t you tell me about the accident?
- How did you do that?
NOTE: The auxiliary did is used to form the negative and interrogative forms.
Here are the spelling rules: