Just when the magnetic field will flip is impossible to predict from what is known at the moment; the best guess is that there are still several centuries to go.

到底什么时候磁极将会颠倒从目前已知的证据中去预测还不能做到，但对此最适宜的猜测便是那一天的到来是好几个世纪以后的事情了。

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Each handles some of the deadliest organisms known to man and animals: diseases that are highly infectious, fatal even in low doses and impossible to treat.

每所实验室都负责研究一些在人类和动物身上已发现的最致命的生物体：具有高度传染性的疾病，哪怕是很小剂量也会致命，而且绝无治疗的可能。

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Ellison also should have known it is impossible to shut up Marc Benioff.

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After the 10 February robbery, Mr Gloor said the works were so well known that it would be impossible to try and sell them on the open market.

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Barofsky kept insisting that TARP be tied to additional lending when he should have known that was impossible.

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