( Matter ( ( ( is either ) ( ( ( a mixture ) or ) ( a ( pure substance ) ) ) ) . ) )
(ROOT (S (NP (NNP Matter)) (VP (VBZ is) (ADVP (RB either)) (NP (NP (DT a) (NN mixture)) (CC or) (NP (DT a) (JJ pure) (NN substance)))) (. .)))
Matter is either a mixture or a pure substance.
(ROOT (S (NP (NNS Elements)) (VP (VBP are) (NP (NP (JJ pure) (NNS substances)) (SBAR (WHNP (WDT that)) (S (VP (VBP make) (ADVP (RB up) (DT all) (NN matter))))))) (. .)))