Chuyển các câu sau sang "not until ......."
1. The children didn’t do their homework until their teacher came back. ……………………………………………………………………………………
2. She doesn’t wake up until the alarm clock goes off. ……………………………………………………………………………………
3. He wasn’t famous until the age of 30. ……………………………………………………………………………………
4. Hoa hasn’t finished her task until 9 o’clock. ……………………………………………………………………………………
5. It didn’t stop raining until an hour ago. ……………………………………………………………………………………
6. Nam and his brother couldn't swim until they were 10. ……………………………………………………………………………………
7. I don’t have to wear uniform until I go to school. ……………………………………………………………………………………
8. We didn’t have any part-time job until we entered the university. ……………………………………………………………………………………
9. No one cleaned this room until I moved here. …………………………………………………………………………………… 
10. He didn’t return to his native village until the war ended. ………………………………………………………………………
11. He was unable to take up the post until early the following year. ………………………………………………………………………
12. No one could leave the stadium until 2:30. ………………………………………………………………………………
13. She wasn’t allowed to open her presents until her birthday. …………………………………………………………