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: airport : car. moon : ?
Example Output: rocket

Example Input: school : skateboard. portland : ?
Example Output: car

Example Input: canada : bus. mainland : ?
Example Output:
boat