( ( When ( water ( changes ( from ( a ( ( liquid ( to water ) ) vapor ) ) ) ) ) ) ( , ( it ( ( is ( called evaporation ) ) . ) ) ) )
(ROOT (S (SBAR (WHADVP (WRB When)) (S (NP (NN water)) (VP (VBZ changes) (PP (IN from) (NP (DT a) (ADJP (JJ liquid) (PP (TO to) (NP (NN water)))) (NN vapor)))))) (, ,) (NP (PRP it)) (VP (VBZ is) (VP (VBN called) (NP (NN evaporation)))) (. .)))
When water changes from a liquid to water vapor, it is called evaporation .
(ROOT (S (SBAR (WHADVP (WRB When)) (S (NP (JJ liquid) (NN water) (NNS changes)) (VP (TO to) (VP (VB water) (NP (NN vapor)))))) (NP (PRP it)) (VP (VBZ is) (VP (VBN called) (NP (NN evaporation)))) (. .)))
When liquid water changes to water vapor it is called evaporation.