它必须能够在极端环境下正常工作。

It must work in extreme conditions.

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加固复合型鞋底：在极端环境下延长鞋子的寿命。

Reinforced with extended wear compound in outsoles, wear longer for performance in extreme environment.

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在极端环境下，可有效防寒，保持足部温暖舒适。

Insulate against the cold, keep your foot warm and comfortable while tackling extreme conditions.

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But beyond the extremes, additions or subtractions to our external circumstances make very little difference.

但在这些极端情况之外，增加或减少的外部环境,产生的区别很小。

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