Yawn - Wikipedia The English yawn continues a number of Middle English forms: yanen from Old English ġānian, and yenen, yonen from Old English frequentatives ġinian, ġionian, from a Germanic root *gīn-
Why Do We Yawn? - WebMD When you yawn, a wetting agent known as a surfactant coats the tiny air sacs (alveoli) in your lungs, which helps keep them open
yawn(英文单词)_百度百科 This accords with anecdotal evidence that people often yawn in situations where they are neither tired nor bored, but are preparing for impending mental and physical activity
YAWN在剑桥英语词典中的解释及翻译 - Cambridge Dictionary A two-hour meeting - what a yawn! Frankly, most of these shows are a yawn So far, the contest has been a total yawn His latest album is, sadly, a yawn that lacks the verve of his debut
YAWN 释义 | 柯林斯英语词典 - Collins Online Dictionary 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 She yawned, and stretched lazily
Yawning Definition Causes - Cleveland Clinic When you yawn, several muscles in your face tense and stretch Sometimes, this can pull on and stimulate your lacrimal glands, which leads to tears and watery eyes