6. think _ thought 

7. put _ put

8. give _gave 

9. write _ wrote 

10. be _ was/were 

11. buy _ bought 

12. have _ had 

13. take  _ took 

14. go _ went 

15. make _ made

16. cut _cut 

17. see _ saw 

18. eat _ ate

19. drink _ drank 

20. wear _ wore