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9. They couldn't leave the stadium until 2.30.
10. She isn't allowed to open her presents until her birthday.
11. We didn't go swimming until last summer.
12. wasn't interested in film unti!! saw the first one.
13. She didn't stay up late until she reviewed for the final examination.
14. They didn't know his news until 2008
15. I didn't write to him until I got a letter from him.
16. He didn't study English until he was in grade 6
17. I didn't believe him until he told the truth.
18. Susan didn't come to evening classes until I asked.
19. My sister didn't speak English fluently until she practiced regularly.