( ( Other metals ) ( ( ( ( are ( highly reactive ) ) and ) ( ( combine easily ) ( with ( ( ( other elements ) , ) ( such ( as oxygen ) ) ) ) ) ) . ) )
(ROOT (S (NP (JJ Other) (NNS metals)) (VP (VP (VBP are) (ADJP (RB highly) (JJ reactive))) (CC and) (VP (VBP combine) (ADVP (RB easily)) (PP (IN with) (NP (NP (JJ other) (NNS elements)) (, ,) (PP (JJ such) (IN as) (NP (NN oxygen))))))) (. .)))
Other metals are highly reactive and combine easily with other elements, such as oxygen.
(ROOT (S (NP (JJ Reactive) (NNS elements)) (VP (VBP are) (ADJP (JJ able) (S (VP (TO to) (VP (VB combine) (ADVP (RBR more) (RB easily)) (PP (IN with) (NP (JJ other) (NNS elements)))))))) (. .)))