1. I'm absolutely sure.
2. I'm positive that...
3. I have no doubt that...
4. I'm a hundred percent certain.
5. I'm convinced that...
6. Chances are that... (= this will probably happen)
7. Odds are that... (= this will probably happen)
8. I seriously doubt it.
9. I don't think so.
10. Probably not.
11. It's not very likely.
12. There's not much chance of that.
13. I'd be very surprised if that happened.
14. I wouldn't bet on it. (= there's a small chance it could happen... but it probably won't happen)
15. That'll never happen.

Awesome Literary T Shirts

Oliver Spencer Braxted Cotton T Shirt

Oliver Spencers block tshirt remains understated, despite the use of contrasting colours. Its made from pure cotton, too, so its breathable.