( ( Unlike ( the ( Sked stretcher ) ) ) ( , ( ( the Half-Sked ) ( ( allows ( the ( patient ( to ( ( ( bend ( at ( the hips ) ) ) , ) ( ( allowing ( greater flexibility ) ) ( to ( turn corners ) ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN Unlike) (NP (DT the) (NNP Sked) (NN stretcher))) (, ,) (NP (DT the) (NN Half-Sked)) (VP (VBZ allows) (NP (DT the) (NN patient) (S (VP (TO to) (VP (VB bend) (PP (IN at) (NP (DT the) (NNS hips))) (, ,) (S (VP (VBG allowing) (NP (JJR greater) (NN flexibility)) (S (VP (TO to) (VP (VB turn) (NP (NNS corners)))))))))))) (. .)))
Unlike  the Sked stretcher, the Half-Sked allows the patient to bend at the hips, allowing greater flexibility to turn corners.
(ROOT (S (NP (NP (DT The) (NN flexibility)) (PP (IN of) (NP (DT an) (NN object)))) (VP (VBZ allows) (S (NP (PRP it)) (VP (TO to) (VP (VB bend))))) (. .)))
The flexibility of an object allows it to bend.