( Rotate ( ( ( refers ( to ( ( ( movement ( around ( ( an ( object 's ) ) ( own ( ( axis or ) center ) ) ) ) ) : ) ( ( &#147; ( Earth rotates ) ) ( on ( its axis ) ) ) ) ) ) ( once ( each day ) ) ) . ) )
(ROOT (S (NP (NNP Rotate)) (VP (VBZ refers) (PP (TO to) (NP (NP (NP (NN movement)) (PP (IN around) (NP (NP (DT an) (NN object) (POS 's)) (JJ own) (NNS axis) (CC or) (NN center)))) (: :) (NP (NP (CD &#147;) (NN Earth) (NNS rotates)) (PP (IN on) (NP (PRP$ its) (NNS axis)))))) (NP (RB once) (DT each) (NN day))) (. .)))
Rotate refers to movement around an object's own axis or center: &#147;Earth rotates on its axis once each day.
(ROOT (S (NP (NNP Earth)) (VP (VBZ rotates) (PP (PP (IN on) (NP (PRP$ its) (NNS axis)) (ADVP (RB once))) (CC times) (PP (IN in) (NP (CD one) (NN day))))) (. .)))