最初它只是由东海岸十三个小殖民地组成，但在先后攫取得克萨斯、亚利桑那、新墨西哥，并于1846年从墨西哥取得加利福尼亚之后，最终扩张到整个北美。
It began as 13 small colonies clinging to the Eastern Seaboard, but eventually expanded across North America, seizing Texas, Arizona, New Mexico, and California from Mexico in 1846.
在亚利桑那州和新墨西哥州，多亏实行了圈养繁殖，墨西哥狼这一濒临灭绝的亚种的数量正在缓慢地增长，虽然它们仍然前途未卜。
Still on shaky ground, the Mexican gray Wolf, an endangered subspecies, is slowly increasing in number in Arizona and New Mexico, thanks to captive breeding.
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