Si te apetece comer algo especial, díselo a María. Es ella quien prepara la cena los sábados.If you want to eat something special, tell Maria. It's her who makes dinner on Saturdays.
Mi padre es quien prepara la cena todos los días porque a mi madre no le gusta cocinar.My father is the one who makes dinner every day because my mother doesn't like cooking.
Mi amigo Roberto, quien prepara la cena esta noche, es cocinero de profesión.My friend Roberto, the one who's making dinner this evening, is a professional cook.