( ( While ( ( many insects ) ( have ( ( a ( four ( stage ( life cycle ) ) ) ) ( -LRB- ( ( complete metamorphosis ) -RRB- ) ) ) ) ) ) ( , ( these ( ( undergo ( only ( ( a ( three ( stage ( life cycle ) ) ) ) ( called ( gradual metamorphosis ) ) ) ) ) . ) ) ) )
(ROOT (S (SBAR (IN While) (S (NP (JJ many) (NNS insects)) (VP (VBP have) (NP (NP (DT a) (CD four) (NN stage) (NN life) (NN cycle)) (PRN (-LRB- -LRB-) (NP (JJ complete) (NNS metamorphosis)) (-RRB- -RRB-)))))) (, ,) (NP (DT these)) (VP (VBP undergo) (SBAR (RB only) (S (NP (DT a) (CD three) (NN stage) (NN life) (NN cycle)) (VP (VBD called) (NP (JJ gradual) (NNS metamorphosis)))))) (. .)))
While many insects have a four stage life cycle (complete metamorphosis), these undergo only a three stage life cycle called gradual metamorphosis.
(ROOT (S (NP (NNS Cells)) (VP (VBP have) (NP (CD four) (NNS cycles))) (. .)))