写出下列单词的过去式形式。

1. buy_________________ 3. bring_________________ 5. arrive_________________ 7. forget_________________ 9. can_________________ 11. skate_________________ 13. say_________________ 15. put_________________ 17. go_________________ 19. is_________________ 2. do_________________ 4. make_________________ 6. come_________________ 8. teach_________________ 10. will_________________ 12. take_________________ 14. have_________________ 16. see_________________ 18. eat_________________ 20. grow _________________

1. bought 2. did 3. brought 4. made 5. arrived 6. came 7. forgot 8. taught 9. could 10. would 11. skated
12. took 13. said 14. had 15. put 16. saw 17. went 18. ate 19. was 20. grew