Hiccups are an uncontrollable contraction of the diaphragm muscle that we use to draw air into our lungs.

打嗝是横膈膜肌肉无法控制的收缩，我们用它把空气吸入肺部。

Sleep apnea stops diaphragm muscles from contracting.

睡眠呼吸暂停会阻止横膈膜肌肉收缩。

That's because the diaphragm muscle lowers during inspiration, and that creates negative pressure in the chest to bring in air, and that negative pressure also brings a bit more venous blood back to the right atrium and right ventricle.

这是因为吸气时膈肌下移，胸腔内的负压将空气吸入；这个负压同时将一些静脉血倒吸回右心房和右心室。