A future perfect?

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Across
  1. 2. a gift of money to someone
  2. 5. to disagree in opinion
  3. 6. a question
  4. 8. to deduct a certain amount from (a bill, etc)
  5. 10. a small routine or job
  6. 11. a passage or quotation taken from a book, etc.
  7. 13. firmly implanted
  8. 15. straight, vertical
  9. 16. made certain by persuasion
  10. 17. to attach firmly
  11. 18. to run away from danger or pursuers
Down
  1. 1. a bright flame or fire
  2. 3. noticeably cold
  3. 4. exaggerated
  4. 7. to think; to calculate
  5. 8. something that one should pay to another
  6. 9. a complete cessation of movement
  7. 12. to go in search of
  8. 14. an investigation