企鹅把翅膀当作鳍来使用。

　　它们很擅长游泳,但却不会飞行。

　　有的鸟,如新西兰几维鸟,也不会飞行。

　　There are some birds that cannot fly. Penguins use their wings as flippers. They can swim well, but they cannot fly. Birds, such as the New Zealand kiwi, cannot fly.

　　大型鸟类,如鸵鸟和鸸鹋,由于体重过大也不能飞行。

　　虽然鸵鸟不会飞,但它能以每小时50公里的速度奔跑。

　　它也可以用它强壮的腿猛烈地踢打敌人。

　　Large birds, such as the ostrich and emu, cannot fly because they are too heavy. Although the ostrich cannot fly, it can run at 50 kilometres per hour. It can also kick its enemies very hard with its strong legs.