( -- ( ( Glenn ========================================================= ) ( ( Once ( per ( ( day , ) ( the earth ) ) ) ) ( ( rotates ( about ( its axis ) ) ) . ) ) ) )
(ROOT (S (: --) (NP (NNP Glenn) (NNP =========================================================)) (ADVP (RB Once) (PP (IN per) (NP (NP (NN day)) (, ,) (NP (DT the) (NN earth))))) (VP (VBZ rotates) (PP (IN about) (NP (PRP$ its) (NNS axis)))) (. .)))
---Glenn ========================================================= Once per day, the earth rotates about 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))))) (. .)))