( ( ( Air bubbles ) ( trapped ( in ( the ( fur help ) ) ) ) ) ( ( keep ( them ( warm underwater ) ) ) . ) )
(ROOT (S (NP (NP (NNP Air) (NNS bubbles)) (VP (VBN trapped) (PP (IN in) (NP (DT the) (NN fur) (NN help))))) (VP (VBP keep) (S (NP (PRP them)) (VP (VB warm) (NP (JJ underwater))))) (. .)))
Air bubbles trapped in the fur help keep them warm underwater.
(ROOT (S (NP (DT An) (JJ underwater) (NN spider)) (VP (VBZ uses) (NP (JJ shiny) (NN air) (NN bubble) (S (VP (TO to) (VP (VP (VB breathe)) (CC and) (VP (VB keep) (ADJP (JJ alive)))))))) (. .)))