But remarkably little is known about the nature of this movement of people one way, and money the other, not least because so much is undocumented or illegal.

但引人注目的是人们对这场人向左钱往右的流动的性质知之甚少，相当重要的原因是太多的流动未登记在册或者说是非法的。

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Peacekeepers airlifted them to a nature reserve to help reduce illegal trading in endangered species.

维和人员将它们空运至一个自然保护区以帮助减少濒危物种的非法买卖。

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The imposition of administrative penalty shall be based on fact and corresponded with the facts, nature, circumstances and harm to the society of the illegal acts.

实施行政处罚，应当以事实为根据，与违法行为的事实、性质、情节以及社会危害程度相当。

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The nature of illegal downloading makes it extremely difficult to track its full extent, but the study's findings are fully conclusive in at least one regard: piracy remains a massive issue.

BBC: A glimpse at piracy in the UK and beyond

That only 1 percent of the bets made on March Madness are placed in one of the four states where sports betting is legalized demonstrates the widespread nature of illegal sports betting.

FORBES: The Business Of The Bracket: How Vegas And Businesses Capitalize On March Madness

Evidence continues to pile up that his News International underlings sought to alert Murdoch to the nature and scale of illegal activities at the News of the World as long ago as 2008.

FORBES: James Murdoch Steps Back at News Corp. Is It Lachlan's Time?