( Volume ( ( is ( ( ( the amount ) ( of space ) ) ( ( an object ) ( ( ( takes up ) , ) ( while ( mass ( is ( ( the amount ) ( of ( matter ( in ( an object ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NN Volume)) (VP (VBZ is) (NP (NP (DT the) (NN amount)) (PP (IN of) (NP (NN space))) (SBAR (S (NP (DT an) (NN object)) (VP (VBZ takes) (PRT (RP up)) (, ,) (SBAR (IN while) (S (NP (NN mass)) (VP (VBZ is) (NP (NP (DT the) (NN amount)) (PP (IN of) (NP (NP (NN matter)) (PP (IN in) (NP (DT an) (NN object)))))))))))))) (. .)))
Volume is the amount of space an object takes up, while mass is the amount of matter in an object.
(ROOT (S (NP (DT The) (NN term) (NN volume)) (VP (VBZ means) (SBAR (S (NP (NP (DT the) (NN amount)) (PP (IN of) (NP (NN space) (NN matter)))) (VP (VBZ takes) (PRT (RP up)))))) (. .)))