underground system

基本解释

Visit our ticket office and buy one of the travel cards that permit you to travel all over the underground system.
請光臨我們的售票処，選擇購買一張允許你乘坐倫敦地鉄系統所有地鉄線的乘車卡。
Beijing's east-west metro line used to terminate at Xidan. Its long-awaited eastward extension in the summer of 2002 was accompanied by numerous changes in the Beijing underground system.
北京東西線地鉄以前的終點站是西單，2002年夏季期待已久的曏東延伸帶來了地鉄系統的很多變化。
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London – the oldest. The first line was thepartially underground Metropolitan Railway Line which opened in 1863, and isnow a part of the more expansive London Underground system.
最古老的地鉄——倫敦地鉄。開通於1863年的倫敦市地下鉄路是倫敦地鉄的前身。這一段開通於那個年代的地鉄已經成爲了正在日益擴張的倫敦地鉄系統的一部分。

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.
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.
在這裡我們所不明白的是，是否真的存在一個,提供地下的,私密的通信服務的，秘密郵政系統。
耶魯公開課 - 1945年後的美國小說課程節選
His idea started when he heard two religious workers playing music for free in New York City's underground transportation system.

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