( ( ( ( ( As ( ( a tadpole ) ( begins ( to ( transform ( into ( a frog ) ) ) ) ) ) ) ( , ( they ( begin ( ( ( developing lungs ) , ) feet ) ) ) ) ) and ) ( they ( loose ( their tales ) ) ) ) . )
(ROOT (S (S (SBAR (IN As) (S (NP (DT a) (NN tadpole)) (VP (VBZ begins) (S (VP (TO to) (VP (VB transform) (PP (IN into) (NP (DT a) (NN frog))))))))) (, ,) (NP (PRP they)) (VP (VBP begin) (NP (NP (VBG developing) (NNS lungs)) (, ,) (NP (NNS feet))))) (CC and) (S (NP (PRP they)) (VP (VBZ loose) (NP (PRP$ their) (NNS tales)))) (. .)))
As a tadpole begins to transform into a frog, they begin developing lungs, feet and they loose their tales.
(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))))))) (. .)))