To their good fortune, he's proving them right.
( ( To ( their ( good fortune ) ) ) ( , ( he ( ( 's ( proving ( them right ) ) ) . ) ) ) )
(ROOT (S (PP (TO To) (NP (PRP$ their) (JJ good) (NN fortune))) (, ,) (NP (PRP he)) (VP (VBZ 's) (VP (VBG proving) (S (NP (PRP them)) (ADJP (RB right))))) (. .)))
He is showing that they are wrong.
( He ( ( is ( showing ( that ( they ( are wrong ) ) ) ) ) . ) )
(ROOT (S (NP (PRP He)) (VP (VBZ is) (VP (VBG showing) (SBAR (IN that) (S (NP (PRP they)) (VP (VBP are) (ADJP (JJ wrong))))))) (. .)))