fight to the last ditch

... 背基骨 = basidorsal 背城借一 = fight to the last ditch 背城借一 = make a last-ditch stand before the city wall ...

 put up a desperate struggle

... 背城借一 = make a last-ditch stand before the city wall 背城借一 = put up a desperate struggle 背凹了 = swayback ...