( Mammals ( ( can ( be ( classified ( as ( carnivores ( , ( ( herbivores and ) omnivores ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNS Mammals)) (VP (MD can) (VP (VB be) (VP (VBN classified) (PP (IN as) (NP (NNS carnivores) (, ,) (NNS herbivores) (CC and) (NNS omnivores)))))) (. .)))
Mammals can be classified as carnivores, herbivores and omnivores.
(ROOT (S (NP (NNS Mammals)) (VP (MD may) (RB either) (VP (VB be) (NP (NNS herbivores) (, ,) (NNS omnivores) (CC or) (NNS herbivores)))) (. .)))