Because it'll equalize the pressure between the atria and the ventricle, and they need to be at different pressures.

因为它会平衡心房和心室之间的压力，而且它们需要处于不同的压力下。

One way that modern bridges avoid flutter is to include a gap in the center of the deck so that the pressures on either side can equalize.

现代桥梁避免颤振的一种方法是在桥面板的中心留出一个间隙，以便两侧的压力能够平衡。

Never Open a Window. If you're one of those people who believe that opening windows during a storm equalizes the pressure and prevents them from shattering, it might be time to revise your beliefs.

切勿打开窗户。如果你相信在暴风雨中打开窗户可以平衡压力并防止其破碎，也许是时候改变你的想法了。

The diaphragm contracts and descends with each inhalation (inspiration). The downward movement of the diaphragm enlarges the area in the thoracic cavity and reduces the internal air pressure, so that air flows into the lungs to equalize the pressure.

每次吸气（吸入）隔膜收缩并下降。隔膜向下运动扩大胸腔内的面积并降低内部气压，使空气流入肺部以平衡压力。