anyone can register a .cat domain and you don't need it in their language, though it may be against their "rules"
edit: Quite puzzled that this is being downvoted. The comment I responded to is suggesting to disregard the TLD's rules when registering domains. You certainly can do that but as far as I understand it is a form of fraud (you are materially misrepresenting yourself and your situation to the TLD). Realistically probably the worst that will happen to you is that your domain will get yanked if they figure it out but that might well be a problem for you and regardless it doesn't change that what you did likely violated multiple laws.