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A lot of people in America are wearing the same clothes ,and many of them have long hair ,sosometimes you don't know who are men and who are women .
One day ,an old man goes for a walk in a park ,and when he is tired ,he sits down on a chair beside a pool . He sees a young person standing on the other side of the pool . "My dear !" the old man says to the person next to him , "Do you see that person in a red sweater and with long hair ? Is it a boy or a girl ?" "A boy ,"says his neighbour , "he is my son ." "Oh !" says the old man , "I'm sorry ,I don't know you are his mother ." "I'm not ," says the other person , "I'm his father ."