( ( ( The speed ) ( of ( a wave ) ) ) ( ( is ( calculated ( by ( ( the product ) ( of ( the ( ( frequency and ) wavelength ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NN speed)) (PP (IN of) (NP (DT a) (NN wave)))) (VP (VBZ is) (VP (VBN calculated) (PP (IN by) (NP (NP (DT the) (NN product)) (PP (IN of) (NP (DT the) (NN frequency) (CC and) (NN wavelength))))))) (. .)))
The speed of a wave is calculated by the product of the frequency and wavelength.
(ROOT (S (NP (NP (DT The) (NN product)) (PP (IN of) (NP (NP (NP (DT a) (NN wave) (POS 's)) (NN wavelength)) (CC and) (NP (PRP$ its) (NN frequency))))) (VP (VBZ is) (NP (PRP$ its) (NN speed))) (. .)))