( ( ( ( Materials and ) Methods ) ( Given ( ( ( an ( unknown species ) ) ( of ( ( bacterium , ) ( the ( ( ( first and ) ( most important ) ) test ) ) ) ) ) ( to ( distinguish ( among ( two types ) ) ) ) ) ) ) ( ( is ( the ( Gram stain ) ) ) . ) )
(ROOT (S (NP (NP (NNS Materials) (CC and) (NNS Methods)) (PP (VBN Given) (NP (NP (DT an) (JJ unknown) (NN species)) (PP (IN of) (NP (NP (NN bacterium)) (, ,) (NP (DT the) (ADJP (ADJP (JJ first)) (CC and) (ADJP (RBS most) (JJ important))) (NN test)))) (S (VP (TO to) (VP (VB distinguish) (PP (IN among) (NP (CD two) (NNS types))))))))) (VP (VBZ is) (NP (DT the) (NNP Gram) (NNP stain))) (. .)))
Materials and Methods Given an unknown species of bacterium, the first and most important test to distinguish among two types is the Gram stain .
(ROOT (S (NP (NNS Bacteria)) (VP (VBP are) (NP (NP (DT the) (RBS most) (JJ numerous) (NNS species)) (PP (IN on) (NP (DT the) (NN planet))))) (. .)))