You're right, travelling is great but it's not just foreign languages that get you in trouble. After I'd worked in London for a couple of weeks I came back from a shopping trip and announced that I was excited about buying a new pair of pants after backpacking for six months with only one pair. When I pulled them out of the bag someone gently explained that I'd bought trousers. . . pants are what you wear underneath them.
Ithink it was Mark Twain who said "two countries divided by a common language"