( ( Centripetal force ) ( ( allows ( an ( object ( to ( maintain ( circular motion ) ) ) ) ) ) . ) )
(ROOT (S (NP (JJ Centripetal) (NN force)) (VP (VBZ allows) (NP (DT an) (NN object) (S (VP (TO to) (VP (VB maintain) (NP (JJ circular) (NN motion))))))) (. .)))
Centripetal force allows an object to maintain circular motion.
(ROOT (S (NP (JJ Centripetal) (NNS forces)) (VP (VBP cause) (S (NP (NNS objects)) (VP (TO to) (VP (VB turn) (PRT (RP around)) (ADVP (RB continuously)) (PP (IN in) (NP (DT a) (NN circle))))))) (. .)))