Prefix Puzzle

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Across
  1. 3. on,upon,over,at,after
  2. 5. not
  3. 6. to,toward,near
  4. 8. from,out
  5. 10. back,backwards
  6. 13. abnormal,bad
  7. 14. one,alone
  8. 15. within,inside
  9. 18. bad,wrong,hate
Down
  1. 1. around,about
  2. 2. one
  3. 4. between,among,across
  4. 6. from,away,off
  5. 7. reduce,away,down,remove
  6. 9. under,below
  7. 11. equal,equally
  8. 12. again
  9. 14. bad,ill,wrong
  10. 16. no,not,without
  11. 17. all