So you have native language , you have region , and then you have time spent in English speaking country. Now , I wonder if it might be useful to have another open field saying " which one parenthesis S  paren closed parenthesis ". Cuz if they spent  time in  in Britain and America
Yes.
It doesn't have to be ex all  at all exact , just in the same open field format that you have.
Yep , just which one. I think that 's fine.