(NP-SBJ-2 
  (-NONE- *pro*))
                    
(VP 
  (VV 可能)
                    
  (VP 
    (VC 是)
                    
    (VP 
      (LB 被)
                    
      (IP-OBJ 
        (NP-SBJ 
          (NN 歹徒))
                    
        (VP 
          (VV 掳走)
                    
          (NP-OBJ 
            (-NONE- *-2)))))
arg0: 
                    歹徒          
                
arg1: 
                    *-2 -> *pro*