Last Saturday Mr. Ma and his wife went out to take a walk. They came back at eight in the evening. When they walked to the front door, Mr. Ma said, "Listen, I can hear someone in the living room." "Yes, you are right," said Mrs. Ma. "There are two men there. They are talking." Then they shouted, "Who's there?" But no one answered. Mr. Ma opened the door quickly and turned on the light. There was nobody! Then Mr. Ma laughed. The TV was still on. "Oh, I forgot to turn it off."