i was looking in the bbrae tag a minute ago and thanks to one post i suddenly love the idea of beast boy being able to speak french
in the post it mentioned that his parents were geneticists, and that they moved around a lot. since they were in africa a lot, which has a lot of french speaking countries, beast boy picked up some of the french and just???
it was from a fanfiction and i cANT FIND IT JSLAJSDK
i really love that idea though, gotta find that fanfiction
Personally, I have the headcanon that BB is a bit of a polyglot, not just from growing up in Africa but traveling all over the world as a member of the Doom Patrol.
Some of the languages he knows is Swahili, French, bits and pieces of Arabic, bits of Portuguese and Spanish (which is very helpful when speaking with Mas and Menos), even offhand knowledge of Latin from studying animal classifications.