(IP 
  (NP-SBJ 
    (NN 死因))
                    
  (VP 
    (VC 是)
                    
    (NP-PRD 
      (CP 
        (WHNP-1 
          (-NONE- *OP*))
                    
        (CP 
          (IP 
            (NP-TPC 
              (NN 早产儿))
                    
            (NP-SBJ 
              (-NONE- *T*-1))
                    
            (VP 
              (ADVP 
                (AD 最))
                    
              (VP 
                (VA 致命))))
                    
          (DEC 的)))
                    
      (NP 
        (NN 肺出血)))))
arg0: 
                    *T*-1 	  
                
argM: 
                    早产儿 	  
                
argm: 
                    最