Wiens ouders komen de kamer in? - Haar ouders komen de kamer in. - "come <the room> in" not "come in <the room>" If we use your sentence "Wiens ouders komen in de kamer?" You ask whose parents come in the room, as in, if they ever go to that room. I assumed you wanted to ask "Whose parents are coming into the room?" Van wie komen de ouders de kamer in? - De ouders van Ria komen de kamer in. - same mistake for this one. Wiens zoon leert op school? - Hun zoon leert op school. - correct! "Whose son learns at school?" - "Their son learns at school" Van wie leert zoon op school? - this translates to "from who does son learn at school?" (answer would be 'from his teacher') But you want to ask "Whose son learns at school?" Which you already correctly used above "Wiens zoon leert op school?" "De zoon van meneer Jansen leert op school." - Correct!