Filter by language in survey - by: upgradeit

Could somebody tell me if it's possible to do this?:
In the survey there's two languages, each contact Is asigned to a predefined languages, although at the beginning of the survey it can be changed the language. What i need to do Is filter a question according if it answer for an language or the other one.
It could be in revelance equation or checked it with javascript and proceed to the next question from browser.