beat up and down

And if we now beat up and down . . . we have the possibility to fly like a bird.

如果上下拍打的话那它就有可能像鸟儿一样飞起来了。

The robot's wings not only beat up and down, but also twist at specific angles along the wingspan in the same way that a real bird does.

智能鸟的翅膀不仅能上下拍打，还能和真正的鸟类一样沿着翼展方向扭转一定的角度。

They beat up and down for truth.

他们为寻求真理而东奔西忙。

Its wings not only beat up and down, but also twist at specific angles.

它的翅膀不但可以上下拍打而且能够在一定角度内翻转。