英语谜语九 Riddles9

51.What goes all over the house,but touches nothing?
52.What belongs only to you and yet is used more by others than by yourself?
53.Which letter of the alphabet separates Europe from Africa?
54.Why is a river rich?
55.I have cities but no houses,forests but no trees; rivers but without water;what am I?
56.A man jumped from a plane,but there was nothing wrong with him.Do you know why?
57.In a train,a woman saw other peoples' faces were dirty. What would she do,do you know?
58.Why did John say he didn't know where the sun was?
59.Where does a person stay for the longest time in his life?
60.Why does Tom's mother go to work by plane every day?