1. If you`ve ever watched a hummingbird or seen a bat chase after a moth, you know that critters that flap their wings to fly are amaing aerial acrobats, capable of hovering near a flower or turning on a dime.
如果你曾经观察过蜂鸟，或者你看过蝙蝠追逐飞蛾的话，那么你可能知道靠振动翅膀飞行的动物是令人拍案叫绝的空中杂技演员，它们能在花朵上盘旋，也能迅速翻转。