( ( ( ( ( A reading ) ( of 7 ) ) ( is neutral ) ) ( -LRB- ( ( ( pure water ) ( has ( ( a pH ) ( of 7 ) ) ) ) -RRB- ) ) ) . )
(ROOT (S (S (NP (NP (DT A) (NN reading)) (PP (IN of) (NP (CD 7)))) (VP (VBZ is) (ADJP (JJ neutral)))) (PRN (-LRB- -LRB-) (S (NP (JJ pure) (NN water)) (VP (VBZ has) (NP (NP (DT a) (NN pH)) (PP (IN of) (NP (CD 7)))))) (-RRB- -RRB-)) (. .)))
A reading of 7 is neutral (pure water has a pH of 7).
(ROOT (S (NP (CD 7)) (VP (VBZ is) (NP (NP (DT the) (NN ph)) (PP (IN of) (NP (JJ pure) (NN water))))) (. .)))