( ( ( The energy ) ( produced ( by ( these vibrations ) ) ) ) ( ( is ( ( carried ( to ( your ( friend ( s ear ) ) ) ) ) ( by ( ( sound waves ) ( traveling ( through ( ( ( a medium ) , ) air ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NN energy)) (VP (VBN produced) (PP (IN by) (NP (DT these) (NNS vibrations))))) (VP (VBZ is) (VP (VBN carried) (PP (TO to) (NP (PRP$ your) (NN friend) (NN s) (NN ear))) (PP (IN by) (NP (NP (JJ sound) (NNS waves)) (VP (VBG traveling) (PP (IN through) (NP (NP (DT a) (NN medium)) (, ,) (NP (NN air))))))))) (. .)))
The energy produced by these vibrations is carried to your friend s ear by sound waves traveling through a medium, air.
(ROOT (S (PP (IN Like) (NP (NP (DT the) (NNS strings)) (PP (IN of) (NP (NN cello))))) (, ,) (NP (NP (NN anything)) (SBAR (WHNP (WDT that)) (S (VP (VBZ vibrates))))) (VP (VBZ produces) (NP (NP (NNS waves)) (PP (IN of) (NP (NN energy))))) (. .)))