( ( As some ) ( ( f ( ( the ice ) ( ( turns ( to ( ( a ( gassy tail ) ) ( from ( ( the ( comet 's ) ) proximity ) ) ) ) ) ( to ( the sun ) ) ) ) ) ( , ( ( the comet ) ( ( releases ( ( a trail ) ( of ( dust ( and ( rocky debris ) ) ) ) ) ) . ) ) ) ) )
(ROOT (S (PP (IN As) (NP (DT some))) (SBAR (X (SYM f)) (S (NP (DT the) (NN ice)) (VP (VBZ turns) (PP (TO to) (NP (NP (DT a) (JJ gassy) (NN tail)) (PP (IN from) (NP (NP (DT the) (NN comet) (POS 's)) (NN proximity))))) (PP (TO to) (NP (DT the) (NN sun)))))) (, ,) (NP (DT the) (NN comet)) (VP (VBZ releases) (NP (NP (DT a) (NN trail)) (PP (IN of) (NP (NN dust) (CC and) (JJ rocky) (NN debris))))) (. .)))
As some f the ice turns to a gassy tail from the comet's proximity to the sun, the comet releases a trail of dust and rocky debris.
(ROOT (S (NP (JJ Comet) (NNS tails)) (VP (ADVP (RB always)) (VBP point) (PRT (RP away)) (PP (IN from) (NP (NP (DT the) (NN sun)) (PP (RB instead) (IN of) (S (VP (VBG trailing) (PP (IN behind) (NP (DT the) (ADJP (JJ comet) (PP (IN because) (NP (NN dust) (NNS particles)))) (NN recoil))))))))) (. .)))