Ответ:

  1. It was warm, so I took off my coat.
  2. The film wasn't very good. I didn't enjoy it very much.
  3. I knew Sarah was very busy, so I didn't disturb her.
  4. I was very tired, so I went to bed early.
  5. The bed was very uncomfortable. I didn't sleep very well.
  6. Sue wasn't hungry, so she didn't eat anything.
  7. We went to Kate's house but she wasn't at home.
  8. It was a funny situation but nobody laughed.
  9. The window was open and a bird flew into the room.
  10. The hotel wasn't very expensive. It didn't cost very much.

В утвердительных предложениях использована форма Simple Past, а в отрицательных — didn't + начальная форма глагола. Глагол be имеет форму was/were, а неправильные глаголы имеют формы took, went, flew.