When I see a bird that walks like a duck and swims like a duck and quacks like a duck, I call that bird a duck.

When I see a bird that walks like a duck and swims like a duck and quacks like a duck, I call that bird a duck.

当我看到一只像鸭子一样走路，像鸭子一样游泳，像鸭子一样嘎嘎叫的鸟时，我叫它鸭子。

-- James Whitcomb Riley 詹姆斯·惠特科姆·莱利