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     A lot of boys and girls in western countries are wearing the same clothes, and many boys have long hair, so it is difficult to tell whether they are boys or not.

      One day an old man went for a walk in a park in Washington and when he was tired, he sat down on a chair by a swimming pool. A young person was standing on the other side of the pool.

     “Oh!” the old man said to the person sitting next to him, “Do you see the person with the loose clothes and long hair? Is it a boy or a girl?”

     “A girl,” said the person, “She is my daughter.”

     “Oh!” the old man said quickly, “Please forgive me. I don't know that you are her mother. ”

     “I'm not,” said the person, “I'm her father.”