( Evaporation ( ( is ( ( the process ) ( of ( ( changing ( liquid water ) ) ( into ( ( water vapor ) ( -LRB- ( ( a gas ) -RRB- ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Evaporation)) (VP (VBZ is) (NP (NP (DT the) (NN process)) (PP (IN of) (S (VP (VBG changing) (NP (JJ liquid) (NN water)) (PP (IN into) (NP (NP (NN water) (NN vapor)) (PRN (-LRB- -LRB-) (NP (DT a) (NN gas)) (-RRB- -RRB-))))))))) (. .)))
Evaporation is the process of changing liquid water into water vapor (a gas).
(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.