PURPOSE: To automatically decide a language used for an area shown by position information only by inputting the position information and to set the class of first and second languages based on this decided result.

CONSTITUTION: Based on the position information expressed by a latitude and a longitude inputted to a position information input part 1, a language class decision part 3 retrieves a position language class information recording part 2 and sends the class of the language obtained by the result of retrieval to a language class setting part 4 and based on this result, the language class setting part 4 sets the first and second languages at a language conversion part 5.