( ( ( Approaching ( nonlinear dynamics ) ) ( by ( studying ( ( the motion ) ( of a. ) ) ) ) ) . )
(ROOT (S (VP (VBG Approaching) (NP (NN nonlinear) (NNS dynamics)) (PP (IN by) (S (VP (VBG studying) (NP (NP (DT the) (NN motion)) (PP (IN of) (NP (NN a.)))))))) (. .)))
Approaching nonlinear dynamics by studying the motion of a..
(ROOT (S (NP (NNP Dynamics)) (VP (VBZ is) (NP (NP (DT the) (NN study)) (PP (IN of) (SBAR (WHADVP (WRB how)) (S (NP (NNS forces)) (VP (VBP affect) (NP (NP (DT the) (NN motion)) (PP (IN of) (NP (NNS objects)))))))))) (. .)))
Dynamics is the study of how forces affect the motion of objects.