( Oxygen ( ( is ( ( produced ( by ( ( algae ( and ( other plants ) ) ) ( in ( ( the presence ) ( of sunlight ) ) ) ) ) ) ( through ( ( a process ) ( called photosynthesis ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Oxygen)) (VP (VBZ is) (VP (VBN produced) (PP (IN by) (NP (NP (JJ algae) (CC and) (JJ other) (NNS plants)) (PP (IN in) (NP (NP (DT the) (NN presence)) (PP (IN of) (NP (NN sunlight))))))) (PP (IN through) (NP (NP (DT a) (NN process)) (VP (VBN called) (NP (NN photosynthesis))))))) (. .)))
Oxygen is produced by algae and other plants in the presence of sunlight through a process called photosynthesis .
(ROOT (S (NP (NNP Oxygen)) (VP (VBZ is) (VP (VBN made) (PP (IN by) (NP (NP (NNS trees)) (CC and) (NP (JJ other) (NNS plants)))) (PP (IN during) (NP (NN photosynthesis))))) (. .)))