"Who ate my cheese sandwich?"
Translation:¿Quién comió mi sándwich de queso?
in Spain, at least if you ask for un sandwich de queso, you will be given a sandwich made with soft square sliced bread ( the one that is sold in a square plastic bag like BIMBO ) and sliced melting cheese like HOCHLAND. but if you ask for a bocadillo de queso you will be given a sandwich made with baguette bread or similar breads and portions of authentic cured and consistent cheese like manchego. it is difficult to me explain this issue but if you type in google images sandwich de queso and bocadillo de queso you will clearly see what i am trying to explain. i do not know if this is valid in other hispanic countries. I would like to take this opportunity to ask them about how they call these concepts. pd. If BIMBO and HOCHLAND are interested in paying me for this advertising I will be glad to pass them my account number in private.
Who is the subject of this sentence, so ¿Quién? is used. Who knows? ¿Quién sabe?
Who has my pen? ¿Quién tiene mi bolígrafo?
A quién makes who (whom!) the object of the sentence. Who(m) are you going to invite? ¿A quién vas a invitar? Who(m) does he love? ¿A quién ama él?