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1. It was not until all the seats were full that the play began.
2. It was until he was 5 that my son started walking.
3. It was not until 1930s that the electric guitar was developed for pop music.
4. It was not until their teacher came that the boy stopped singing.
5. It was not until she received a letter from him that she wrote to him.
6. It was not until I had all the information that I could comment furrther.
7. Not until the bell rang did he finish his work.
8. Not until I asked a passer-by did I know where I was.
9. Not until next Friday will she see him.
10. Not until the rain stopped could they go on working.
11. Not until I went to bed did I remember the task.
12. Not until the early 1960s did man fly into space.
13. Not until she was 18 did she go abroad.

14. Not until they were robbed of money did they become more careful.
15. If we had had a map, we wouldn't have got lost.
16. If you don't stop walking, you won't understand the lesson.
17. If I knew her number, I would ring her up.
18. If he hadn't been too lazy, he wouldn't have got fired.
19. If she didn't feel very tired today, she could cook.
20. If you don't follow the instruction, you will ruin everything.
21. Unless he were very ill, he would be at work.
22. Unless I liked singing, I would not join this club.

23. Unless he apologizes to me, I won't be on his team.
24. If you don't stop eating, you won't be sick.