Here’s a list of common prefixes that may appear on the October Digital SAT:

1. un- (not)

2. re- (again)

3. in- (not)

4. dis- (opposite of)

5. pre- (before)

6. post- (after)

7. mis- (wrongly)

8. sub- (under)

9. inter- (between)

10. trans- (across)

11. super- (above)

12. anti- (against)

13. semi- (half)

14. ex- (out of)

15. non- (not)

16. pro- (for)

17. contra- (against)

18. over- (excessive)

19. under- (below)

20. bi- (two)

21. tri- (three)

22. multi- (many)

23. omni- (all)

24. hypo- (under)

25. hyper- (over)

These prefixes are commonly used in English vocabulary.