( ( In ( ( tortoises and ) turtles ) ) ( , ( ( the ribs ) ( ( are ( fused ( to ( a ( rigid shell ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (NNS tortoises) (CC and) (NNS turtles))) (, ,) (NP (DT the) (NNS ribs)) (VP (VBP are) (VP (VBN fused) (PP (TO to) (NP (DT a) (JJ rigid) (NN shell))))) (. .)))
In tortoises and turtles, the ribs are fused to a rigid shell.
(ROOT (S (NP (JJS Most) (NN turtle) (NNS bodies)) (VP (VBP are) (VP (VBN covered) (PP (IN by) (NP (NP (DT a) (JJ special) (NN bony) (CC or) (NNS cartilaginous) (NN shell)) (VP (VBN developed) (PP (IN from) (NP (PRP$ their) (NNS ribs)))))))) (. .)))