( ( ( The speed ) ( of ( a wave ) ) ) ( ( is ( equal ( to ( ( ( ( ( the product ) ( of ( ( its wavelength ) ( times ( its frequency ) ) ) ) ) , ) or ) ( ( its wavelength ) ( divided ( by ( its period ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NN speed)) (PP (IN of) (NP (DT a) (NN wave)))) (VP (VBZ is) (ADJP (JJ equal) (PP (TO to) (NP (NP (NP (DT the) (NN product)) (PP (IN of) (NP (NP (PRP$ its) (NN wavelength)) (PP (CC times) (NP (PRP$ its) (NN frequency)))))) (, ,) (CC or) (NP (NP (PRP$ its) (NN wavelength)) (VP (VBN divided) (PP (IN by) (NP (PRP$ its) (NN period))))))))) (. .)))
The speed of a wave is equal to the product of its wavelength times its frequency, or its wavelength divided by its period.
(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))) (. .)))