( ( Mercury Mercury ) ( ( is ( ( the ( 1st planet ) ) ( to ( the sun ) ) ) ) . ) )
(ROOT (S (NP (NNP Mercury) (NNP Mercury)) (VP (VBZ is) (NP (NP (DT the) (JJ 1st) (NN planet)) (PP (TO to) (NP (DT the) (NN sun))))) (. .)))
Mercury Mercury is the 1st planet to the sun.
(ROOT (S (NP (NNP Mercury)) (VP (VBZ is) (ADJP (ADJP (JJS closest)) (PP (TO to) (NP (DT the) (NN sun))))) (. .)))