Sometimes this can cause dangerous or even fatal reactions.

有时会造成危险，甚至危及生命。

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Flu symptoms can be severe, and even fatal, when the illness strikes young children or the elderly.

当病毒攻击幼儿或老人时，流感症状可能很严重甚至是致命的。

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And in our culture of quick wins and instant gratification, failure can be harmful — or even fatal — to your career.

而在我们急功近利的文化中，对您的职业生涯来说，失败会产生不利影响，或者甚至是致命的。

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Legislators have redrawn congressional districts into such partisan playing fields that moderation is politically dangerous, even fatal.

CNN: Fiscal cliff was bound to collapse

It is harmless to humans and is not even fatal to most animals, but it destroys their economic value.

CNN: Seven new UK foot-and-mouth cases

Speaking of Giuliani, his decision to forgo the early primaries looked like a poorly considered, even fatal mistake last week.

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