( ( ( ( ( ( Other planets ) ( have water ) ) , ) but ) ( they ( either ( ( have it ) ( as ( ( ( ( ( a gas ) ( -LRB- ( Venus -RRB- ) ) ) or ) ice ) ( -LRB- ( Mars -RRB- ) ) ) ) ) ) ) ) . )
(ROOT (S (S (NP (JJ Other) (NNS planets)) (VP (VBP have) (NP (NN water)))) (, ,) (CC but) (S (NP (PRP they)) (ADVP (RB either)) (VP (VBP have) (NP (PRP it)) (PP (IN as) (NP (NP (DT a) (NN gas)) (PRN (-LRB- -LRB-) (NP (NNP Venus)) (-RRB- -RRB-)) (CC or) (NP (NN ice)) (PRN (-LRB- -LRB-) (NP (NNP Mars)) (-RRB- -RRB-)))))) (. .)))
Other planets have water, but they either have it as a gas (Venus) or ice (Mars).
(ROOT (S (NP (NNP Water)) (VP (VBZ takes) (NP (NP (DT the) (NN form)) (PP (IN of) (NP (NN ice)))) (PP (IN on) (NP (NN planet) (NNS mars)))) (. .)))