( ( Ultrasound ( ( Sound waves ) ( that ( are ( inaudible ( to ( the ( human ear ) ) ) ) ) ) ) ) . )
(ROOT (S (VP (VB Ultrasound) (NP (NP (JJ Sound) (NNS waves)) (SBAR (WHNP (WDT that)) (S (VP (VBP are) (ADJP (JJ inaudible) (PP (TO to) (NP (DT the) (JJ human) (NN ear))))))))) (. .)))
Ultrasound Sound waves that are inaudible to the human ear.
(ROOT (S (NP (PRP You)) (VP (VBP call) (NP (NP (NN sound)) (SBAR (WHNP (WDT that)) (S (VP (VBZ has) (S (NP (DT a) (NN wave) (NN frequency)) (ADJP (JJR higher) (SBAR (IN than) (S (NP (DT the) (JJ human) (NN ear)) (VP (MD can) (VP (VB detect) (NP (NN ultrasound))))))))))))) (. .)))