( Earth ( ( is ( ( the ( only place ) ) ( in ( ( the ( solar system ) ) ( where ( ( ( ( ( liquid water ) , ) ( essential ( to ( life ( as ( we ( know it ) ) ) ) ) ) ) , ) ( exists ( at ( the surface ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Earth)) (VP (VBZ is) (NP (NP (DT the) (JJ only) (NN place)) (PP (IN in) (NP (NP (DT the) (JJ solar) (NN system)) (SBAR (WHADVP (WRB where)) (S (NP (NP (JJ liquid) (NN water)) (, ,) (ADJP (JJ essential) (PP (TO to) (NP (NP (NN life)) (SBAR (IN as) (S (NP (PRP we)) (VP (VBP know) (NP (PRP it)))))))) (, ,)) (VP (VBZ exists) (PP (IN at) (NP (DT the) (NN surface)))))))))) (. .)))
Earth is the only place in the solar system where liquid water, essential to life as we know it, exists at the surface.
(ROOT (S (NP (NNP Earth)) (VP (VBZ is) (NP (NP (DT the) (JJ only) (NN planet)) (PP (IN in) (NP (NP (DT the) (JJ solar) (NN system)) (SBAR (WHNP (WDT that)) (S (VP (VBZ has) (NP (NP (NN water)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBZ is) (ADJP (JJ essential)) (PP (IN for) (NP (JJ human) (NN life))) (, ,) (ADJP (JJ present)) (PP (IN in) (NP (NP (QP (DT all) (CD three))) (PP (IN of) (NP (PRP$ its) (NNS states)))))))))))))))) (. .)))