( ( ( The ( average length ) ) ( of ( ( the ( reproductive cycle ) ) ( for females ) ) ) ) ( ( is ( 6 months ) ) . ) )
(ROOT (S (NP (NP (DT The) (JJ average) (NN length)) (PP (IN of) (NP (NP (DT the) (JJ reproductive) (NN cycle)) (PP (IN for) (NP (NNS females)))))) (VP (VBZ is) (NP (CD 6) (NNS months))) (. .)))
The average length of the reproductive cycle for females is 6 months.
(ROOT (S (NP (JJ Menstrual) (NN cycle)) (VP (VBZ is) (NP (NP (DT the) (NN name)) (PP (IN for) (NP (NP (DT a) (NN series)) (PP (IN of) (NP (NP (NNS changes)) (PP (IN in) (NP (NP (DT the) (JJ reproductive) (NN system)) (PP (IN of) (NP (JJ mature) (NNS females))))))))) (SBAR (WHNP (WDT that)) (S (VP (VBZ repeats) (NP (NP (DT every) (NN month)) (PP (IN on) (NP (NN average))))))))) (. .)))