(ADVP 
  (AD 但))
                    
(NP-SBJ 
  (NP 
    (NN 其中))
                    
  (QP 
    (CD 一))
                    
  (NP 
    (NN 人)))
                    
(VP 
  (PP-PRP 
    (P 因为)
                    
    (IP 
      (NP-SBJ 
        (-NONE- *pro*))
                    
      (VP 
        (VV 滑倒))))
                    
  (VP 
    (LB 被)
                    
    (IP-OBJ 
      (NP-SBJ 
        (NN 歹徒))
                    
      (VP 
        (VV 砍伤)
                    
        (NP-OBJ 
          (NN 背部)))))))
argm: 
                    但          
                
arg1: 
                    其中 一 人          
                
argm: 
                    因为 滑倒          
                
arg0: 
                    歹徒          
                
arg1: 
                    背部