(IP 
  (NP-SBJ 
    (-NONE- *pro*))
                    
  (VP 
    (ADVP 
      (AD 约))
                    
    (PP 
      (P 比)
                    
      (NP 
        (NN 头发)))
                    
    (VP 
      (VA 细)
                    
      (QP-EXT 
        (CD 一)
                    
        (CLP 
          (M 倍))))))
arg0: 
                    *pro* 
                
argm: 
                    一 倍 
                
argm: 
                    比 头发 
                
argm: 
                    约