( ( ( Neon ( , ( argon ( , ( krypton ( , ( and xenon ) ) ) ) ) ) ) also ) ( ( form ( ( ( clathrate hydrates ) , ) ( where ( ( the ( noble gas ) ) ( is ( trapped ( in ice ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (NN Neon) (, ,) (NN argon) (, ,) (NN krypton) (, ,) (CC and) (NN xenon)) (ADVP (RB also))) (VP (VBP form) (NP (NP (JJ clathrate) (NNS hydrates)) (, ,) (SBAR (WHADVP (WRB where)) (S (NP (DT the) (JJ noble) (NN gas)) (VP (VBZ is) (VP (VBN trapped) (PP (IN in) (NP (NN ice))))))))) (. .)))
Neon, argon, krypton, and xenon also form clathrate hydrates, where the noble gas is trapped in ice.
(ROOT (S (NP (NNP Neon)) (VP (VBZ is) (NP (NP (DT an) (NN example)) (PP (IN of) (NP (JJ noble) (NN gas))))) (. .)))