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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Passengers on Moscow's underground system can now access a toilet for the first time - but only at one station.

莫斯科地铁系统的乘客现在终于能用上卫生间了，这还是破天荒头一遭，不过只有一个站点设了卫生间。

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Rotterdam does have a nice underground system which was perfect for our third test.

鹿特丹出众的地下运输系统为我们的第三轮测试提供了合适的场地。

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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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