Yet last summer several houses along the route suddenly sank a few centimetres without warning.Their occupants, alerted by the cracking, escaped through windows.All underground work was halted.

• 然而，在去年夏天，工程线路沿线的几栋房子没有任何征兆地就下沉了几厘米，听到破裂声的房主们纷纷从窗口逃了出去，所有的工程由此暂停。