Many bad smells can be very superficial.

很多“坏味道”是很容易嗅出来的。

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The system will also be able to detect various other bad smells - such as from animals and factories - and will automatically switch the ventilation on if required.

该系统还有探测各种来自动物或工厂不良气味的功能，并且能够按照需要自动打开换气装置。

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Bad smells are not just a matter of poor hygiene. Illness and old age both bring characteristic odours of their own, and neither state makes people more attractive.

难闻的味道不光是不卫生的问题，疾病和衰老都具有各自的特色气味；不过上面的这两种情况都不能增加人的吸引力，但是香水却可以粉饰上述问题。

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Avoid the temptation to say, "Well, poop smells bad because it's so stinky."

避免这样回答，嗯，大便闻起来不好,因为它很臭“

耶鲁公开课 - 心理学导论课程节选

Within a year of the buyout, there were again bad smells and clouds of flies.

FORBES: Magazine Article

"You can make antagonists to bad smells, " Snyder says.

FORBES: The Secrets of Scent

He probably smells bad, but the only one who seems to notice is the oldest child, a girl, thirteen.

NEWYORKER: Midnight in Dostoevsky