The phrase "请问您是吗" in English can be translated as "May I ask if you are?" or "Could it be that you are?" This expression is often used in formal situations to confirm someone's identity. For example, if a receptionist is unsure about the person at the door, they might say, "May I ask if you are here to see Mr. Smith?" or if a customer service representative is trying to verify a caller's identity, they might ask, "Could it be that you are the owner of this account?"