( Hydrogen ( ( is ( ( ( ( the ( ( most abundant ) element ) ) ( in ( ( ( the ( universe ( , ( and oxygen ) ) ) ) ( is ( either ( ( 3rd or ) 5th ) ) ) ) ( most abundant ) ) ) ) ( -LRB- ( ( I ( ( ( do n't ) ( remember which ) ) ... ) ) -RRB- ) ) ) 2 ) ) . ) )
(ROOT (S (NP (NNP Hydrogen)) (VP (VBZ is) (NP (NP (NP (DT the) (ADJP (RBS most) (JJ abundant)) (NN element)) (PP (IN in) (NP (NP (NP (DT the) (NN universe) (, ,) (CC and) (NN oxygen)) (SBAR (S (VP (VBZ is) (ADJP (DT either) (JJ 3rd) (CC or) (JJ 5th)))))) (ADJP (RBS most) (JJ abundant))))) (PRN (-LRB- -LRB-) (NP (NP (PRP I)) (SBAR (S (VP (VBP do) (RB n't) (VP (VB remember) (WHNP (WDT which)))) (: ...)))) (-RRB- -RRB-)) (NP (CD 2)))) (. .)))
Hydrogen is the most abundant element in the universe, and oxygen is either 3rd or 5th most abundant (I don't remember which...) 2.
(ROOT (S (NP (DT The) (NN element) (NN hydrogen)) (VP (VBZ is) (NP (NP (DT the) (RBS most) (JJ abundant)) (PP (IN in) (NP (DT the) (NN universe))))) (. .)))
The element hydrogen is the most abundant in the universe.