( This ( ( is ( why ( ( kinetic energy ) ( is ( ( the energy ) ( of motion ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT This)) (VP (VBZ is) (SBAR (WHADVP (WRB why)) (S (NP (JJ kinetic) (NN energy)) (VP (VBZ is) (NP (NP (DT the) (NN energy)) (PP (IN of) (NP (NN motion)))))))) (. .)))
This is why kinetic energy is the energy of motion.
(ROOT (S (NP (NNP Kinetic)) (ADVP (RB engergy)) (VP (VBZ is) (NP (NP (DT the) (NN energy)) (PP (IN of) (NP (NP (NN anything)) (PP (IN in) (NP (NN motion))))))) (. .)))