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    The first United States airmail stamp has had an interesting story. Printed in 1918,this 24-cent stamp with a blue plane inside a rose border became the center of much attention.One hundred of the stamps sold to the public became known as "inverts",for the plane was printed upside down.Some of these "upside-down" airmail stamps are now worth over $6,000.

    关于美国的第一枚航空邮票有一个有趣的故事。这枚面值为24美分的邮票印刷于1918年，玫瑰花边的中间有一架蓝色的飞机，成为人们关注的中心。因为蓝色的飞机被印颠倒了，仅仅有一百枚这种“倒转”邮票卖给公众。现在，有些这种“倒转”航空邮票价值超过6000美元。