听力文本

There is a curse that has plagued humanity since ancient times.
从古代起就有一种“诅咒”一直让人类饱受折磨。
The Greeks fought it by chewing aromatic resins, while the Chinese resorted to egg shells.
古希腊人通过咀嚼芳香树脂来对抗它，而古代的中国人使用的则是鸡蛋壳。
In the ancient Jewish Talmud, it's even considered legal grounds for divorce.
在古犹太法典中，它甚至成为了合法的离婚理由。
This horrible scourge is halitosis, otherwise known as bad breath.
这种可怕的折磨就是口气异常，也被称为口臭。
But what causes it, and why is it so universally terrifying?
但是它是如何产生的呢？为什么它如此普遍地令人生畏？
Well, think of some of the worst odors you can imagine, like garbage, feces or rotting meat.
想一想你能想象到的一些最难闻的气味，比如垃圾、排泄物或者腐坏的肉。

All of these smells come from the activity of microorganisms, particularly bacteria, and,
所有这些味道都来自微生物，特别是细菌的活动，
as disgusting as it may sound, similar bacteria live in the moisture-rich environment of your mouth.
尽管听起来很恶心，但是相似的细菌就生活在你的嘴里这个湿润的环境中。
Don't panic. The presence of bacteria in your body is not only normal,
别慌。细菌存在于你的身体中不仅再正常不过了，
it's actually vital for all sorts of things, like digestion and disease prevention.
而且事实上，它对很多事情都是至关重要的，比如消化和疾病预防。
But like all living things, bacteria need to eat.
但是和所有活着的事物一样，细菌需要进食。
The bacteria in your mouth feed off of mucus, food remnants, and dead tissue cells.
你嘴里的细菌以粘液、食物残渣和死亡的组织细胞为食。
In order to absorb nutrients through their cell membranes,
为了通过它们的细胞膜吸收养分，
they must break down the organic matter into much smaller molecules.
这些细菌必须把有机质分解成更小的分子。

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