(IP (ADVP (AD 不过))
(PU ，)
(NP-SBJ (NN 知识)
(CC 和)
(NN 创意))
(VP (VP (VC 是)
(NP-PRD (CP (WHNP-1 (-NONE- *OP*))
(CP (IP (NP-SBJ (-NONE- *T*-1))
(VP (VA 无形)))
(DEC 的)))))
(PU ，)
(VP (ADVP (AD 很))
(ADVP (AD 难))
(VP (VV 证明)
(NP-OBJ (NN 所有权)
(NN 归属))))))
ARG0: *T*-1
REL: 无形