( Metallurgy ( ( distinguishes ( between ( ( ( Bronze alloys ) , ) ( which ( contain ( ( ( ( mainly ( ( Copper and ) Tin ) ) , ) and ) ( ( Brass alloys ) ( which ( contain ( ( Copper and ) Zinc ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Metallurgy)) (VP (VBZ distinguishes) (PP (IN between) (NP (NP (NN Bronze) (NNS alloys)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBP contain) (NP (NP (RB mainly) (NN Copper) (CC and) (NN Tin)) (, ,) (CC and) (NP (NP (NNP Brass) (NNP alloys)) (SBAR (WHNP (WDT which)) (S (VP (VBP contain) (NP (NNP Copper) (CC and) (NNP Zinc))))))))))))) (. .)))
Metallurgy distinguishes between Bronze alloys, which contain mainly Copper and Tin, and Brass alloys which contain Copper and Zinc.
(ROOT (S (NP (NN Bronze)) (VP (VBZ is) (NP (NP (DT an) (NN alloy)) (PP (IN of) (NP (NN copper) (CC and) (NN tin))))) (. .)))