Polar bears cannot survive without sea ice, using it to raise their young, to travel and as a platform for hunting seals - their primary food source.

没有海冰，北极熊就无法生存。 它们需要利用海冰来抚养幼仔，四处漫游，并以此为平台捕猎它们的主要食物，海豹。

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Polar bears are threatened because they use sea ice as a platform from which to hunt seals. But a warming climate brings many problems for the Inuit.

气候变暖让北极熊受到威胁是因为他们需要冰海来捕捉海豹，但是一个暖和的气候对因纽特人会带来很多麻烦。

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