8. is / change: are9. bạn làm đúng rồi
10. bạn làm đúng rồi
11. have / change: has12. bạn làm đúng rồi
13. was / change: were14. is / change: are15. bạn làm đúng rồi
16. is / change: are17. admire / change: admires18. bạn làm đúng rồi
19. were / change: was20. are / change: is