Consider that there were underground millionaire entrepreneurs in the former Soviet Union when owning private property and employing people outside of the state system was a prison offense.

想想前苏联那些地下百万富翁们，当时拥有私人财产并雇用别人来工作可是违法的。

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Native Chinese Xiuli Hawken, now a UK citizen, registers fifth, her wealth coming from property and from running shopping centres in China in spaces converted from underground military shelters.

排行榜第五位，英籍华裔秀丽•好肯（原名戴秀丽，后嫁英国老公改姓，生于哈尔滨——译者注），她的财富来自房地产和运营由防空洞（military shelters）改成的购物中心。

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Prior to construction, delineate and mark all property boundaries and underground utilities.

在建造之前，画出并标出所有的财产边界和地下设备。

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Two unnamed "people familiar with the matter" told Bloomberg that the hackers appeared to be looking for research, intellectual property or other private information that they can sell on the underground market.

CNN: Doug Gross,

This is no accident: the place was built from the ground up to be the best, with no expense spared, including extensive hidden underground tunnels so you never see maids or room service staff walking around the low rise, spread out property.

FORBES: Las Ventanas al Paraiso, Los Cabos, Mexico