( ( As ( tadpoles ( grow ( into frogs ) ) ) ) ( , ( lungs ( ( ( ( replace ( the gills ) ) and ) ( allow ( frogs ( to ( breathe ( on land ) ) ) ) ) ) . ) ) ) )
(ROOT (S (SBAR (IN As) (S (NP (NNS tadpoles)) (VP (VBP grow) (PP (IN into) (NP (NNS frogs)))))) (, ,) (NP (NNS lungs)) (VP (VP (VB replace) (NP (DT the) (NNS gills))) (CC and) (VP (VB allow) (S (NP (NNS frogs)) (VP (TO to) (VP (VB breathe) (PP (IN on) (NP (NN land)))))))) (. .)))
As tadpoles grow into frogs, lungs replace the gills and allow frogs to breathe on land.
(ROOT (S (NP (DT A) (NN frog)) (VP (VBZ develops) (NP (PRN (-LRB- -LRB-) (NP (NN a/an)) (-RRB- -RRB-)) (NNS lungs)) (SBAR (IN as) (S (NP (PRP it)) (VP (VBZ changes) (PP (IN from) (NP (DT a) (NN tadpole))) (PP (TO to) (NP (DT an) (JJ adult) (NN frog))))))) (. .)))