Short Answers
| Question | Affirmative | Negative |
|---|---|---|
| Do we know him? | Yes, we do. | No, we don't. |
| Can she see me? | Yes, she can. | No, she can't. |
| Have they read the book? | Yes, they have. | No, they haven't. |
| Is he hungry? | Yes, he is. | No, he isn't. |
Saying ‘Yes, I do. / No, I don’t’ in English is more polite than just saying ‘Yes. / No.’ That’s why short answers are very commonly used.
To form the short answer, you use the first word from the question.
Use the long form (he does) in affirmative answers (yes).
Use the short form (he doesn’t) in negative answers (no).
Ángulo 
