( ( Define ( ( frequency ( , ( ( wavelength and ) speed ) ) ) ( of ( a wave ) ) ) ) . )
(ROOT (S (VP (VB Define) (NP (NP (NN frequency) (, ,) (NN wavelength) (CC and) (NN speed)) (PP (IN of) (NP (DT a) (NN wave))))) (. .)))
Define frequency, wavelength and speed of a wave.
(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))) (. .)))