"Where is he living?"
Translation:Cá bhfuil sé ina chónaí?
Took me a while to find these "standard rules":
her: no initial mutation,
From an Ulster Irish (Gaeilig Uladh) point of view, would "Cá háit a bhfuil sé ina chónaí?" not be acceptable?
As an example of similar: "Cá háit a bhfuil an LYIT?" - on the Letterkenny Institute of Technology website. I've seen similar usage via Foras na Gaeilge with "Cá háit ar domhan a bhfuil an Róimh?".
I have written them out on a sheet of paper so I have them beside me to help me figure which one to use.Might work for you too.