( ( To ( maintain ( good health ) ) ) ( , ( ( regular exercise ) ( ( is required ) . ) ) ) )
(ROOT (S (S (VP (TO To) (VP (VB maintain) (NP (JJ good) (NN health))))) (, ,) (NP (JJ regular) (NN exercise)) (VP (VBZ is) (VP (VBN required))) (. .)))
To maintain good health, regular exercise is required.
(ROOT (S (NP (NNP Exercising)) (ADVP (RB regularly)) (VP (VBZ is) (NP (DT a) (JJ good) (NN health) (NN habit))) (. .)))
Exercising regularly is a good health habit.