One afternoon David plays football in front of a house with his classmates. A young woman comes up and asks him, "David, is your father at home?" "Yes, he is." answers the boy. Then the young woman goes to press the bell (按门铃). The bell rings and rings, but no one comes to open the door. The young woman gets angry (生气) and calls to him, "You tell me your father is at home, don't you?" "Yes, my father is at home, but my home isn't here."