A misspelled joke story

Once upon a time, there was an old gentleman named Xue who often put his foot in his mouth. Later, he was accused of teaching something wrong and misleading his children. County grandfather asked: Do you accept punishment or are you willing to fight? Mr. Private School said: Admit the punishment. County grandfather wrote: three chickens, two rabbits. Then tell him that you should deliver it to me before dark according to the list. The old man took it and left, and soon came back with only a chicken. The county magistrate was furious: I want to be punished. The old man said quickly, sir, the villain did as you said. Look, isn't it written: three chickens, two for free?