Words of multiple meaning

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Across
  1. 2. – A person who provides medical treatment OR to alter something
  2. 4. – A piece of writing in its initial form OR air current
  3. 5. – A person who trains athletes OR a type of transport
  4. 6. – To fasten OR to collapse under pressure
  5. 8. – Absolutely sure OR a specific but unknown quantity
  6. 9. – A tradition OR something made specifically for an individual
Down
  1. 1. – To modify something OR a medical professional
  2. 3. – A path for water OR a medium for communication
  3. 5. – To shape stone OR to roughly assemble something
  4. 7. – A small group of advisors OR a storage unit with shelves