Здесь нужно поставить глагол во вторую форму. У всех этих глаголов вторая форма нестандартная.
2. I didn't know - I knew.
3. She didn't throw - She threw.
4. We didn't eat - We ate.
5. It didn't freeze - It froze.
6. We didn't speak - We spoke.
7. They didn't wake up - They woke.
8. He didn't steal - He stole.
