A mother and her young son get into a bus in a small city and sit down. The bus conductor comes to them for their money. The mother says: “I want one ticket____to the zoo ” and gives him one yuan. The conductor looks at the small boy for a few seconds and then says to him, “How old are you ,young man?” The mother begins to speak, but the conductor stops her, The boy says: “Im four at home, and two in the buses.” At last the mother has to take fifty fen out of her pocket and gives it to the conductor.