How to Introduce a Particular Topic

Have you ever heard about . . . Have you ever been to London? Have you ever been in a first flight? Have you ever been on TV? Have you ever been a guest star? Have you ever eaten vegetables? What kind of vegetables have you ever eaten? Have you ever had a camera? Have you ever known about . . . ? Have you ever tasted fried duck? Have you ever felt strange about this place? Has your mother ever cooked noodle?

What do you know about . . .? Do you know fruits? What do you know about fruits? What does your father know about me ? Does he know about History?