(PP-MNR 
  (P 经过)
                    
  (NP 
    (NN 现场)
                    
    (NN 急救)))
                    
(NP-SBJ 
  (-NONE- *pro*))
                    
(VP 
  (ADVP 
    (AD 还是))
                    
  (VP 
    (VV 回天乏术))))
argm: 
                    经过 现场 急救          
                
arg0: 
                    *pro*          
                
argm: 
                    还是