yawning

音标发音

The occupants of the rooms are yawning too, or else scratching themselves.
屋子里注的房客也在打哈欠，或是在替自己搔痒。
Yawning is not just a sign of tiredness or boredom – it is the body's method of keeping our brain cool, scientists have found.
打呵欠不仅是疲劳或厌倦的信号–– 根据科学家的最新发现，它还是人体用来自动调节大脑温度的一种手段。
Although babies begin to yawn spontaneously even before they leave the womb, most of the children in this study didn't show signs of contagious yawning until they were 4.
尽管婴儿甚至在离开娘胎之前开始不由自主地打哈欠，但在这项研究中的大多数孩子直到4岁才开始有打哈欠传染的迹象。

and the USA Today newspaper said there is "a yawning need for clarity" and warned against trying to use half-measures to achieve important goals.
We can't keep shifting a growing burden to future generations. With each passing year, health care costs consume a larger share of our nation's spending, and contribute to yawning deficits that we cannot control,".

Past midnight, Durbin slumped at his desk, one hand over his face, yawning painfully.
NEWYORKER: The Empty Chamber
They'll probably also have to address government spending in the face of an ever-yawning deficit.
NPR: Great Expectations As Candidates Debate Again

used to describe a difference or amount that is extremely large and difficult to reduce

If you yawn, you open your mouth very wide and breathe in more air than usual, often when you are tired or when you are not interested in something.
Yawn is also a noun.