( ( ( ( ( Most ( are ( ( considered ( sexually mature ) ) ( after ( one year ) ) ) ) ) , ) but ) ( often ( ( ( the size ) ( of ( a fish ) ) ) ( indicates ( ( ( its maturity ) ( rather than ) ) time ) ) ) ) ) . )
(ROOT (S (S (NP (JJS Most)) (VP (VBP are) (VP (VBN considered) (NP (RB sexually) (JJ mature)) (PP (IN after) (NP (CD one) (NN year)))))) (, ,) (CC but) (S (ADVP (RB often)) (NP (NP (DT the) (NN size)) (PP (IN of) (NP (DT a) (NN fish)))) (VP (VBZ indicates) (NP (NP (PRP$ its) (NN maturity)) (CONJP (RB rather) (IN than)) (NP (NN time))))) (. .)))
Most are considered sexually mature after one year, but often the size of a fish indicates its maturity rather than time.
(ROOT (S (NP (JJS Most) (NN fish)) (VP (VB reproduce) (PP (IN with) (NP (CD one) (DT another))) (ADVP (RB sexually))) (. .)))