( Xenon ( ( is ( classed ( as ( ( a ( noble gas ) ) ( -LRB- ( ( see ( Noble gas ) ) -RRB- ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Xenon)) (VP (VBZ is) (VP (VBN classed) (PP (IN as) (NP (NP (DT a) (JJ noble) (NN gas)) (PRN (-LRB- -LRB-) (S (VP (VB see) (NP (NNP Noble) (NN gas)))) (-RRB- -RRB-)))))) (. .)))
Xenon is classed as a noble gas (see Noble gas ).
(ROOT (S (NP (NNP Neon)) (VP (VBZ is) (NP (NP (DT an) (NN example)) (PP (IN of) (NP (JJ noble) (NN gas))))) (. .)))