The only time of this construction is used to start a dialogue is when we ask for the whereabouts of someone/something. interrogative-word questions: They are going back to the dorm now. Where are we going? The teacher doesn’t understand it? Whom shall I go ask? Affirmative-negative questions: The grammar for this lesson is hard. You’re a good student. Do you understand the grammar in this lesson? He speaks fluent Chinese. What about Chinese characters? Does he write neatly? Alternative questions: Are you going now or tomorrow? You don’t drink coffee. Then what will you have? Orange juice or tea? He is a teacher who is very conscientious about his work. Come, let me introduce you. Hello, may I ask who you are? You two young ladies, come along. What terrible fish soup you have made, Mister. How many in your party? This is one of the few cases where pragmatics takes priority over linguistic logic.