Common = English
As WotC is an english-based Community run by an english-based company, both chat and boards are english-based.
If you chat or post in languages other than english, you must be aware of how much you use etc. It doesn't matter whether it's Dwarven, High Elven, German, Portugese, Celestial, French, pig latin, etc etc etc., if there is too much of it it may be considered Room Disruption because it can be as annoyoing as anyone writing entirely in caps or entirely in "leet speech".
And let's face it, unless the person is honestly without english and/or is getting help in their own language, the only reason to use
lots of another language is so that others canot understand what you're saying.
Eg: "Pounamu", Marshal of Juxta and tavern maid of the Crossroads has Common as her second language. There are occasional words of her own language in what she says, especially when she's trying to understand something but if she thinks something or says something in her own language, usually it is marked with *maori* but written in English. Every now and then I can get away with a line or two maximum in Maori for her but that's less than once-in-a-blue-moon (usually situations where what she says is supposed to be particularly potent and foreign and translated for anyone who cares to ask).
But if I were to type everything in maori, I'd soon get pulled up for Room Distruption.
What you can do if you're trying to help someone using a language other than english is to keep it in PMs. When a frustrated new player took to portuguese in the Emporium and was past the point of calming for English, I PMed him in Portuguese. (Tell you what, it gave him quite a surprise to see it, too!
) But even if we had been in an ooc room like Live, I wouldn't have struck up conversation in portuguese with him "in the room".
Just keep in mind that even if you're helping someone out, they'll have to switch to english eventually or else they won't get help from anyone else or be able to play. And of course the CoC is still in effect.
If what you're trying to do is have a character speak another language and you don't want others to understand it, (like they would if you said "*elven*{whatever you say written in english}") perhaps you could emote/roleplay the type of gestures and sound but carry the conversation in PMs so that no one can say that they understood.
eg: Pounamu frowns, uttering dark tones of her own language with a sneer
(PMed
"*maori* Perhaps without your undead minions, dark lord, you could do nothing"
