There is absolutely no problem with people speaking multiple languages; just allow people to choose all the languages they speak. In other words, use chechboxes (those things on the right [in this picture](
http://www.java2s.com/Tutorial/VB/0300__2D-Graphics/UseCheckBoxtoSetFont.htm)) instead of radiobuttons (those things on the left and in the middle).
You can even store both (all languages spoken and a preferred language) but that only becomes relevant when you start doing something with it, such as if the interface were ever translated or many maps had descriptions in multiple languages. Needless to say, that might not be very high on Fizzer's priority list (there are a few suggestions about translating the WL interface on UserVoice; multi-language map descriptions aren't on there yet as far as I know, but could always be added).