( It ( ( ( can also ) ( ( assist ( the ( respiratory system ) ) ) ( in ( ( the passage ) ( of air ) ) ) ) ) . ) )
(ROOT (S (NP (PRP It)) (VP (MD can) (ADVP (RB also)) (VP (VB assist) (NP (DT the) (JJ respiratory) (NN system)) (PP (IN in) (NP (NP (DT the) (NN passage)) (PP (IN of) (NP (NN air))))))) (. .)))
It can also assist the respiratory system in the passage of air.
(ROOT (S (NP (NNP Narrow) (NN air) (NNS passages)) (VP (VBP make) (S (VP (VBG breathing) (ADJP (JJ difficult) (RB due) (S (VP (TO to) (VP (VB respiratory) (NP (NN system) (NN disease))))))))) (. .)))