(IP (NP-SBJ (-NONE- *pro*))
(VP (VP (ADVP (AD 往往))
(VP (VV 要)
(VP (LCP-OBJ (IP (NP-SBJ (NN 肾脏))
(VP (VP (VRD (VV 损伤)
(VV 到))
(NP-OBJ (JJ 相当)
(NN 程度)))
(PU ，)
(VP (ADVP (AD 甚至))
(ADVP (AD 只))
(VP (VV 剩下)
(NP-OBJ (QP (CD 四分之一))
(NP (NN 功能)))))))
(LC 时)))))
(PU ，)
(VP (ADVP (AD 才))
(VP (VV 能)
(VP (PP-DIR (P 由)
(LCP (NP (NN 血液))
(LC 中)))
(VP (VRD (VV 检验)
(VV 出来))))))))
ARG1: 肾脏
ARG2: 相当 程度
REL: 损伤