Irregular verbs in past participle

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Across
  1. 3. see
  2. 4. sing
  3. 6. eat
  4. 9. drink
  5. 10. read
  6. 11. run
  7. 15. drive
  8. 16. hear
  9. 17. buy
  10. 18. think
  11. 19. do
Down
  1. 1. know
  2. 2. come
  3. 3. swim
  4. 5. go
  5. 7. take
  6. 8. write
  7. 12. understand
  8. 13. sleep
  9. 14. be
  10. 17. begin