( ( During ( the evaporation ) ) ( , ( liquid ( ( becomes ( water vapor ) ) . ) ) ) )
(ROOT (S (PP (IN During) (NP (DT the) (NN evaporation))) (, ,) (NP (NN liquid)) (VP (VBZ becomes) (NP (NN water) (NN vapor))) (. .)))
During the evaporation, liquid becomes water vapor.
(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.