( ( ( ( ( Ice ( is ( when ( water ( is solid ) ) ) ) ) ( , ( ( steam ( is ( when ( water ( is gas ) ) ) ) ) , ) ) ) and ) ( water ( usually ( refers ( to ( its ( liquid state ) ) ) ) ) ) ) . )
(ROOT (S (S (NP (NNP Ice)) (VP (VBZ is) (SBAR (WHADVP (WRB when)) (S (NP (NN water)) (VP (VBZ is) (ADJP (JJ solid))))))) (PRN (, ,) (S (NP (NN steam)) (VP (VBZ is) (SBAR (WHADVP (WRB when)) (S (NP (NN water)) (VP (VBZ is) (NP (NN gas))))))) (, ,)) (CC and) (S (NP (NN water)) (ADVP (RB usually)) (VP (VBZ refers) (PP (TO to) (NP (PRP$ its) (JJ liquid) (NN state))))) (. .)))
Ice is when water is solid , steam is when water is gas , and water usually refers to its liquid state .
(ROOT (S (NP (NNP Ice)) (VP (VBZ is) (NP (NP (DT the) (JJ common) (NN term)) (PP (IN for) (NP (NP (NN water)) (PP (IN in) (NP (PRP$ its) (JJ solid) (NN state))))))) (. .)))