Video narration
Do you ever build a question, then freeze: is the preposition missing, extra, or wrong? We say, "Where do you live?"-not "Where do you live at?" Here, where asks about place, and live needs no added preposition. But in "Who are you talking to?" to matters. It shows connection with another person, and ending a question with a preposition is natural. The question word does not choose the preposition. Meaning does. Place, time, direction, or connection tells you what relationship you need. Sometimes the choice comes from a verb combination: "What are you interested in?" or "Who are you waiting for?" Learn those together. Ask: Do I need a preposition at all? If yes, does it match the meaning, or belong to this verb combination? Context or dialect can change the choice. So stop guessing from where or who. Choose from the relationship-or the verb's combination.