How many languages do you speak ?
1) How many language do you speak ?
2) What are they ?
3) Which one(s) do you speak fluently ?
4) Which one is your first language ?
5) Do you find usefull to speak more than one language ?
6) Which one (of those you speak) do you find the most difficult ? and in what is it difficult ?
7) What language would you like to learn ?
edit: (two more extra questions i forgot to ask ...)
8) Why did you learn these extra languages ?
9) How often do you use these extra languages ?