由于大部分有关其生活范围的研究还很少，所以很难统计出全球北极能的数量。
It is difficult to figure out a global population of polar bears as much of the range has been poorly studied.
生物都有很广阔的生活范围。
偷猎和栖息地被破坏威胁着非洲象的生活范围。
Poaching and habitat destruction threaten African elephants throughout their range.
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