( cartilage ( ( skeleton 3 ) . ) )
(ROOT (S (NP (NN cartilage)) (VP (VBP skeleton) (NP (CD 3))) (. .)))
cartilage skeleton 3.
(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))))) (. .)))