( ( Mercury ( Venus ( Earth Mars ) ) ) ( There ( ( are ( ( nine ( planets revolving ) ) ( around ( our Sun ) ) ) ) . ) ) )
(ROOT (S (NP (NNP Mercury) (NNP Venus) (NNP Earth) (NNP Mars)) (ADVP (RB There)) (VP (VBP are) (NP (NP (CD nine) (NNS planets) (JJ revolving)) (PP (IN around) (NP (PRP$ our) (NN Sun))))) (. .)))
Mercury Venus Earth Mars There are nine planets revolving around our Sun.
(ROOT (S (NP (NNP Mercury)) (VP (VBZ is) (ADVP (RB always)) (ADJP (ADJP (JJR closer)) (PP (TO to) (NP (DT the) (NN sun)))) (SBAR (IN than) (S (NP (PRP it)) (VP (VBZ is) (PP (TO to) (NP (NN earth))))))) (. .)))
Mercury is always closer to the sun than it is to earth.