( ( Their ( entire skeleton ) ) ( ( is ( made ( of ( ( cartilage , ) ( a ( strong ( flexible ( connective tissue ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (PRP$ Their) (JJ entire) (NN skeleton)) (VP (VBZ is) (VP (VBN made) (PP (IN of) (NP (NP (NN cartilage)) (, ,) (NP (DT a) (JJ strong) (JJ flexible) (NN connective) (NN tissue)))))) (. .)))
Their entire skeleton is made of cartilage, a strong flexible connective tissue.
(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))))) (. .)))