The force upward equals the force downward so that the balloon stays at the level.

向上的力与向下的力相等，所以气球就维持正在这一高度。

youdao

The force upward equals the force downward so that the balloon stays at the level.

向上的力与向下的力相等，所以气球就保持在这一高度。

youdao

But it wasn't necessary to burst the balloon to let out the gas. There are orderly natural processes of readjustment that bring things to their proper level with the least harm to anyone.

但是实在没有必要戳爆这个气球，总有循序渐进的办法来进行重新调整，将物价回调到一个合理的水平，为人们造成最小的伤害。

youdao

Unstable means that if an imaginary balloon filled with air from near the ground were to be lifted upward, colliding with some weather feature such as a cold front, the "balloon" would become warmer than the surrounding air at that level.

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