( Density ( ( ( The amount ) ( of matter ) ) ( ( contained ( within ( a ( given volume ) ) ) ) . ) ) )
(ROOT (S (ADVP (RB Density)) (NP (NP (DT The) (NN amount)) (PP (IN of) (NP (NN matter)))) (VP (VBD contained) (PP (IN within) (NP (DT a) (VBN given) (NN volume)))) (. .)))
Density The amount of matter contained within a given volume.
(ROOT (S (NP (NNP Density)) (VP (VBZ describes) (SBAR (WHADJP (WRB how) (JJ much)) (S (NP (NN matter)) (VP (VBZ is) (PP (IN in) (NP (NP (DT a) (JJ certain) (NN amount)) (PP (IN of) (NP (NN space))))))))) (. .)))