( ( Oxygen ( in water ) ) ( ( is ( used ( by ( ( ( plants ( -LRB- ( ( at night ) -RRB- ) ) ) and ) ( organisms ( in ( the stream ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (NNP Oxygen)) (PP (IN in) (NP (NN water)))) (VP (VBZ is) (VP (VBN used) (PP (IN by) (NP (NP (NP (NNS plants)) (PRN (-LRB- -LRB-) (PP (IN at) (NP (NN night))) (-RRB- -RRB-))) (CC and) (NP (NP (NNS organisms)) (PP (IN in) (NP (DT the) (NN stream)))))))) (. .)))
Oxygen in water is used by plants (at night) and organisms in the stream.
(ROOT (S (NP (NNS Plants)) (VP (CONJP (RB not) (JJ only)) (VP (VBP contribute) (NP (NN food))) (CC but) (VP (VBD oxygen) (PP (IN for) (NP (NNS organisms))))) (. .)))