Cho dạng quá khứ của các động từ sau.

1. do _______________ 11. buy ________________________

2. teach _______________ 12. have ________________________

3. send _______________ 13. take ________________________

4. spend _______________ 14. go ________________________

5. begin _______________ 15. make ________________________

6. cut _______________ 16. think ________________________

7. put _______________ 17. see ________________________

8. give _______________ 18. eat ________________________

9. write _______________ 19. sing ________________________

10. be _______________ 20. wear ________________________