Ответ:

  1. Is it a dog? — Yes, it is.
  2. Do you like tennis?
  3. Did you play tennis yesterday?
  4. Does your sister get up early every day?
  5. Were you at school yesterday?
  6. Are your parents at work now?
  7. Was Nick at the zoo yesterday?
  8. Am I right? — Yes, you are.
  9. Is Pete reading a book now?

Перевод: Is — «является/находится», do/does — вспомогательные глаголы настоящего времени, did — вспомогательный глагол прошедшего времени, am/are/is и was/were — формы глагола to be.