Negative
have / has + not + past participle — no do anywhere.
I have not eaten. → I haven't eaten.
She has not called. → She hasn't called.
Question
Put have or has in front of the subject.
| Statement | Question |
|---|---|
| You have seen it. | Have you seen it? |
| He has arrived. | Has he arrived? |
| They have finished. | Have they finished? |
Short answers
Answer with the same helping verb, not with the main one.
- Have you finished? — Yes, I have. / No, I haven't.
- Has she called? — Yes, she has. / No, she hasn't.
Saying Yes, I have finished is not wrong, only longer than anyone usually bothers with.