( ( In ( a ( direct ( combination reaction ) ) ) ) ( , ( ( ( ( two or ) more ) reactants ) ( ( combine ( to ( form ( a ( single product ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (DT a) (JJ direct) (NN combination) (NN reaction))) (, ,) (NP (QP (CD two) (CC or) (JJR more)) (NNS reactants)) (VP (VBP combine) (S (VP (TO to) (VP (VB form) (NP (DT a) (JJ single) (NN product)))))) (. .)))
In a direct combination reaction, two or more reactants combine to form a single product.
(ROOT (S (NP (DT A) (NN combination) (NN reaction)) (VP (VBZ is) (NP (NP (DT a) (NN reaction)) (SBAR (WHPP (IN in) (WHNP (WDT which))) (S (NP (CD two) (CC or) (JJR more) (NNS substances)) (VP (VBP combine) (S (VP (TO to) (VP (VB form) (NP (DT a) (JJ single) (JJ new) (NN substance)))))))))) (. .)))