( Water ( ( is ( ( the ( only compound ) ) ( that ( commonly ( exists ( in ( ( ( all ( three states ) ) ( -LRB- ( ( ( ( ( solid , ) liquid ) , ) gas ) -RRB- ) ) ) ( on Earth ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Water)) (VP (VBZ is) (NP (NP (DT the) (JJ only) (NN compound)) (SBAR (WHNP (WDT that)) (S (ADVP (RB commonly)) (VP (VBZ exists) (PP (IN in) (NP (NP (NP (DT all) (CD three) (NNS states)) (PRN (-LRB- -LRB-) (NP (JJ solid)) (, ,) (NP (NN liquid)) (, ,) (NP (NN gas)) (-RRB- -RRB-))) (PP (IN on) (NP (NNP Earth)))))))))) (. .)))
Water is the only compound that commonly exists in all three states (solid, liquid, gas) on Earth.
(ROOT (S (NP (NNP Water)) (VP (VBZ exists) (PP (IN on) (NP (NP (NN earth)) (PP (IN in) (NP (NP (CD three) (NN matter) (NNS states)) (VP (VBZ states))))))) (. .)))