A mother and her young son get into a bus in a small city and sit down. The busconductorcomes to them for their money. The mother says, "I want one ticket (票) to the zoo." And she gives her 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, "I'm 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.