When the airlines decided to enforce these rules without giving anyone a heads-up, it created a lot of problems for travellers.

航空公司在决定执行这些规定时没有事先通知任何人，这给旅客带来了很多麻烦。

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These rules are another way to help keep the blood supply pure.

这些规则是帮助保持血液供应纯净的另一种方式。

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These rules provide more detailed information about the relationships and restrictions that exist on the columns of a nickname.

这些规则提供了更详细的信息，是关于存在一个昵称各个列的关系和约束。

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And we have a responsibility to write and enforce these rules to protect consumers of financial products,taxpayers, and our economy as a whole."

VOA: special.2009.09.18

By the 1970s, these rules were rarely enforced and easily violated, or so I was told.

到了七十年代，这种规定已经名存实亡了，至少我听说是这样。

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it's like not so much about following these rules, these guidelines of what you're supposed to do.

这不是循规蹈矩，遵循你该做什么的指导。

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Keep in mind, though, that credit card issuers can start enforcing these rules at any time.

FORBES: Even Affluent Women May No Longer Be Eligible for Credit Cards

And these rules are in addition to the numerous reports and studies that Act also commissioned.

FORBES: Dangers Abound As Financial Reform Goes From Blueprint To Bricks

These rules are boundaries of government, within which our public servants are supposed to solve problems.

FORBES: The Economics of the Mandate Don't Matter: It's Constitutional