I talked about how I develop and keep up with my language skills, interests outside of university e.g. my interest in pilates and yoga, and events or conferences I've been to that haven't been related to university e.g. Shearman & Sterling's women in law conference because diversity within the legal profession, and wider professional services, is important to me.
I put societies in the positions of responsibility question, but I guess if you just attended and didn't necessarily have an executive position then there is probably no reason why it can't go in this question.