The ancestors of the modern Zuni and Hopi built and then, for reasons still mysterious, abandoned the complex roads and structures of the domain they ruled a millennium ago in the American southwest.

一千年前在美国西南部，现代祖尼人和霍皮人的祖先在他们统治的土地上修建了复杂的道路和建筑，后来由于一些不为人所知的原因，又遗弃了这些复杂的道路和建筑。

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Among the reasons for the slower service, today there are more choices on the menu, and the products themselves are more complex and take longer to prepare.

服务速度变慢的原因有：如今菜单上的选择更多了，而且产品本身也更复杂，准备时间更长。

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For complex physiological and biological reasons, this extra fat around the middle causes much greater harm.

由于复杂的物理和生物原因，腰部多余的脂肪会导致更多的危险。

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The result brought him back to earth, reminding him that Italians vote PdL for more complex reasons than blind love of its leader.

ECONOMIST: Berlusconi loses ground

Apparently, for bafflingly complex cultural reasons, today's young people are neglecting to accept jobs.

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This is largely because for a variety of complex reasons, wages tend not to fall fast enough to soak up the extra labor.

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