( ( The ( excess vapor ) ) ( ( ( condenses , ) ( forming ( ( ( ( water droplets ) or ) , ) ( if ( it ( is ( cold ( enough ( , ( ice crystals ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (JJ excess) (NN vapor)) (VP (VBZ condenses) (, ,) (S (VP (VBG forming) (NP (NP (NN water) (NNS droplets)) (CC or) (, ,) (SBAR (IN if) (S (NP (PRP it)) (VP (VBZ is) (NP (JJ cold) (JJ enough) (, ,) (NN ice) (NNS crystals))))))))) (. .)))
The excess vapor condenses, forming water droplets or, if it is cold enough, ice crystals.
(ROOT (S (NP (NP (NNP Dew)) (VP (VBG forming) (PP (IN on) (NP (NNS plants))) (PP (IN during) (NP (DT a) (JJ cold) (NN night))))) (VP (VBZ is) (NP (NP (DT an) (NN example)) (PP (IN of) (NP (NN water) (NN condensing))))) (. .)))