( Plants ( ( ( ( exhale ( Oxygen gas ) ) ( in ( order ( for animals ) ) ) ) ( to breathe ) ) . ) )
(ROOT (S (NP (NNS Plants)) (VP (VBP exhale) (NP (JJ Oxygen) (NN gas)) (PP (IN in) (NP (NP (NN order)) (PP (IN for) (NP (NNS animals))))) (S (VP (TO to) (VP (VB breathe))))) (. .)))
Plants exhale Oxygen gas in order for animals to breathe.
(ROOT (S (NP (NN Oxygen) (NN gas)) (VP (VBZ is) (VP (VBN given) (PRT (RP off)) (PP (IN by) (NP (NNS plants))))) (. .)))