The average hummingbird weighs less than a penny. It has a body temperature of 111 degrees and beats its wings more than 75 times a second. Its newborn are the size of bumblebees and its nest is the size of a walnut. The hummingbird is the only bird that can fly backward.
蜂鸟的平均体重比一枚一便士的硬币还轻。它的体温达111度，翅膀每秒种要扇动75次以上。孵出的蜂鸟只有大黄蜂那么大，其巢只有核桃那么大。蜂鸟是唯一能倒退向后飞的鸟。
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