( Bronze ( ( is ( ( an alloy ) ( made ( of ( ( ( 88 ( percent copper ) ) and ) ( 12 ( percent tin ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NN Bronze)) (VP (VBZ is) (NP (NP (DT an) (NN alloy)) (VP (VBN made) (PP (IN of) (NP (NP (CD 88) (NN percent) (NN copper)) (CC and) (NP (CD 12) (NN percent) (NN tin))))))) (. .)))
Bronze is an alloy made of 88 percent copper and 12 percent tin.
(ROOT (S (NP (NN Bronze)) (VP (VBZ is) (NP (NP (DT an) (NN alloy)) (PP (IN of) (NP (NN copper) (CC and) (NN tin))))) (. .)))