( It ( ( ( ( takes ( 59 ( Earth days ) ) ) ( for Mercury ) ) ( to ( ( rotate once ) ( on ( its axis ) ) ) ) ) . ) )
(ROOT (S (NP (PRP It)) (VP (VBZ takes) (NP (CD 59) (NNP Earth) (NNS days)) (PP (IN for) (NP (NNP Mercury))) (S (VP (TO to) (VP (VB rotate) (ADVP (RB once)) (PP (IN on) (NP (PRP$ its) (NNS axis))))))) (. .)))
It takes 59 Earth days for Mercury to rotate once on its axis.
(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))))) (. .)))