( ( ( ( ( ( Its rotation ) ( about ( its axis ) ) ) ( ( relative ( to ( that motion ) ) ) ( is ( ( the slowest ) ( of ( all ( the planets ) ) ) ) ) ) ) - ) ( it ( takes ( ( Mercury ( about ( 58.6 Earth-days ) ) ) ( to ( complete ( one ( full rotation ) ) ) ) ) ) ) ) . )
(ROOT (S (S (NP (NP (PRP$ Its) (NN rotation)) (PP (IN about) (NP (PRP$ its) (NNS axis)))) (ADVP (JJ relative) (PP (TO to) (NP (DT that) (NN motion)))) (VP (VBZ is) (NP (NP (DT the) (JJS slowest)) (PP (IN of) (NP (PDT all) (DT the) (NNS planets)))))) (: -) (S (NP (PRP it)) (VP (VBZ takes) (S (NP (NP (NNP Mercury)) (PP (IN about) (NP (NNP 58.6) (NNP Earth-days)))) (VP (TO to) (VP (VB complete) (NP (CD one) (JJ full) (NN rotation))))))) (. .)))
Its rotation about its axis relative to that motion is the slowest of all the planets - it takes Mercury about 58.6 Earth-days to complete one full rotation.
(ROOT (S (NP (PRP It)) (VP (VBZ takes) (NP (NN earth) (CD one) (NN week)) (S (VP (TO to) (VP (VB rotate) (PP (IN on) (NP (PRP$ its) (NNS axis))) (NP (CD seven) (NNS times)))))) (. .)))