Wings
翅膀
Birds can fly because they have wings.
鸟儿因为有翅膀才能飞。
Each bird has differently shaped wings.
每种鸟的翅膀的形状都不同。
How fast do birds fly?
鸟能飞得多快呢?
The speed of birds varies.
它们的速度各不相同。
Pigeons fly at a rate of about 35 to 60 miles per hour.
鸽子的飞行速度约35-60英里(约56.3-96.7千米)每小时
And hawks at a rate of about 180 miles per hour.
而鹰的飞行速度约180英里(约289.7千米)每小时。
However, there are some birds which can't fly at all.
然而,有些鸟儿根本就不能飞。
They are penguins and ostriches.
它们就是企鹅和鸵鸟。