So why not take a trip on the oldest underground system today?

所以今天为什么不乘坐世界上最古老的地铁观光一番呢？

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Universal Pictures also said that the posters were not placed near schools and appeared in the London Underground system, which does not have a high proportion of children.

此外，"环球影业"称，宣传海报并没有在学校附近出现，而是投放在儿童很少出现的伦敦地铁里。

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Spec contests have actually created an underground system, whereby some unscrupulous designers will quickly enter as many as possible, as they copy work from the web and present it as their own.

事实上，比稿竞赛已经创造了一个台面下的系统，有些无耻的设计师尽可能地快速投入大量作品，像是从网路抄袭下来当作他们自己的。

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London may be famous for its red double-decker buses, but it is the underground system, parts of it more than a hundred years old, that is especially vulnerable.

VOA: standard.2010.04.01

What we don't get here is a sense of whether there really is an alternate secret postal system that serves a sort of underground of private networks.

在这里我们所不明白的是，是否真的存在一个,提供地下的,私密的通信服务的，秘密邮政系统。

耶鲁公开课 - 1945年后的美国小说课程节选

His idea started when he heard two religious workers playing music for free in New York City's underground transportation system.

VOA: special.2009.07.31

The metro system in particular, only a few years old, can compare with any underground system in the world.

BBC: NEWS | South Asia | Delhi wants Games to provide legacy

Mr Prescott says that much larger sums are needed to provide London with an underground system fit for the 21st century.

ECONOMIST: London Underground

This is not an underground system trying to be hidden from view.

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