Yes, it is possible to have different profile questions for male and female. It is called account types. Please read this manual: http://docs.oxwall.org/user-manual:users:profile-questions the part about account types. 

Thank you. I have red today the entire answer for several points I was wondering about :

http://blog.oxwall.org/2014/02/dev-diary-february-6-2014

I'm sorry I don't understand your last request, please specify

I just want to point out the issues about this matter. The article explains well all what it is about.

Mainly yes, the process of implementing different profile questions to different account types will be smoother and more user-friendly. However, it works right now as well. You can still assign different questions to different account types. 

I just wondered if we could have also a simple thing: sub-questions based on this example :

usually when a user fill a form example : country, he waits some seconds and he is offered to choose, the state, the county or the city which pre-loaded. 

I guess it will possible to do the same at least for radio choices. No ?  

No, this can't be done, you need to choose account type first. 

Ok. Tnx Ross.

I'm going to mark this thread as Solved.