10月初，新的南北线路开通，今年夏天，另外三个也会完工，使得总地铁里程数加倍。
A new north-south line was opened in early October, and three more will be finished this summer, nearly doubling the total mileage of track.
于1900年开通的伦敦中央铁路是这些新线路中最成功的一条。
The central London Railway was one of the most successful of these new lines, and was opened in 1900.
通用航空还使直升飞机救援及救护服务，空中出租车得以开通，并可以方便在边远地区进行维修输电线路，输油管路，及其他基础设施。
General aviation also enables helicopter rescue and ambulance services, air taxis and easier maintenance of power lines, pipelines and other infrastructure in far-flung places.
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