Just some of the many things you could ask would be what is their goal in life, where do they see themselves (and you) in the future, do they want kids and how many, what are their family values as far as loyalty and honesty, those sort of things. And as far as sexual goes, for your own benefit you should both be sure you want to or dont want to have sex before marriage, and what type of relationships they had in the past, how did they turn out, etc. Some people may want to know the others sexual past before they get married.