Two analogies that relate places/locations to the associated travel mode is given in the form "A : B. C : ?". "A : B" relates place A to travel mode B. Your task is to replace the question mark (?) with the appropriate travel mode for the given place C, following the "A : B" relation.

Example Input: park : bicycle. downtown : ?
Example Output: subway

Example Input: island : boat. hawaii : ?
Example Output: airplane

Example Input: downtown : subway. spain : ?
Example Output:
airplane