( ( ( The skeletons ) ( of ( ( sharks and ) rays ) ) ) ( ( are ( ( ( ( composed entirely ) ( of cartilage ) ) , ) ( as ( are ( ( the skeletons ) ( of ( developing embryos ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NNS skeletons)) (PP (IN of) (NP (NNS sharks) (CC and) (NNS rays)))) (VP (VBP are) (VP (VBN composed) (ADVP (RB entirely)) (PP (IN of) (NP (NN cartilage))) (, ,) (SBAR (IN as) (S (VP (VBP are) (NP (NP (DT the) (NNS skeletons)) (PP (IN of) (NP (VBG developing) (NNS embryos))))))))) (. .)))
The skeletons of sharks and rays are composed entirely of cartilage, as are the skeletons of developing embryos.
(ROOT (S (ADVP (RB Early) (PP (IN in) (NP (NP (DT the) (NN development)) (PP (IN of) (NP (DT a) (JJ human) (NN fetus)))))) (, ,) (NP (DT the) (NN skeleton)) (VP (VBZ is) (VP (VBN made) (ADVP (RB entirely)) (PP (IN of) (NP (NN cartilage))))) (. .)))