If you take the subway in Beijing，you may see there's nobody in the driver's seat．But don't be afraid—it just means you are on the new driverless line．September 2017，a driverless subway line(name)the Yanfang Line started to try running in Beijing．The line was open to passengers at end of 2017．The trains on the new line are the Chinese(one)domestically(国内地)made driverless subway cars．The line (build)between Beijing's Yanshan and Fangshan areas with 960 seats and a top speed of 80 (kilometer)per hour. The trains are(complete)self-driven．The general designer says the driverless trains actually run in a(safe)way than regular subway trains．And of course，the "drivers" of the new trains can't become illtired．So far, twelve cities in China(begin)to build such driverless subway lines．