1. We cannot say for sure what will happen.

2. I don't know for sure.

3. I know for sure that...

4. No one knows for sure.

5. That is for sure.

6. I know for sure that I won't be able to go to the party.

7. She's prone to exaggerate, that's for sure.

8. No one knows for sure what happened.

9. The fighting was over for sure.

10. That first test question was a gimme, for sure.

11. No one knows for sure what really happened.

12. We'll always need teachers, that's for sure .

13. One thing's for sure, we'll never be able to move this furniture on our own.

14. One thing's for sure, Astbury's vocal style hasn't changed much over the years.

15. One thing's for sure - once the baby's born, your lives will never be the same again.

16. No one knows for sure why adolescence is unique to humans.

17. Sanders also ain't gonna like it, that's for sure.

18. Certainly not in the Aero-Space industry, that's for sure.

19. She may have jumped, no one knows for sure.

20. No one knows for sure where it began.

21. He wasn't using drugs, that's for sure.

22. It is on for this weekend for sure.

23. Yeah, you'll see him. He'll be there for sure.

24. International business man, that's for sure.

25. I think he'll be back on Monday(Sentencedict.com), but I can't say for sure.

26. I think I can come but I won't commit myself till I know for sure.

27. If you slap your face until it's swollen in an effort to look imposing, you'll suffer for sure.

28. If we could by any possibility manage to do it, we would for sure.

29. I think he's still living in Chicago, but I don't know for sure .

30. I think he lives there but I couldn't say for sure.