( ( ( The ( life cycle ) ) ( for ( one generation ) ) ) ( ( is ( ( ( three to ) four ) years ) ) . ) )
(ROOT (S (NP (NP (DT The) (NN life) (NN cycle)) (PP (IN for) (NP (CD one) (NN generation)))) (VP (VBZ is) (NP (QP (CD three) (TO to) (CD four)) (NNS years))) (. .)))
The life cycle for one generation is three to four years.
(ROOT (S (NP (NNP Life) (NN cycle)) (VP (VBZ is) (NP (NP (DT the) (NN term)) (PP (IN for) (NP (NP (DT the) (NN span)) (PP (IN in) (NP (NP (DT the) (NN life)) (PP (IN of) (NP (NP (DT an) (NN organism)) (PP (IN from) (NP (NP (CD one) (NN generation)) (PP (TO to) (NP (DT the) (JJ next))))))))))))) (. .)))