believing it was just coincidence 
(ROOT (S (VP (VBG believing) (SBAR (S (NP (PRP it)) (VP (VBD was) (NP (RB just) (NN coincidence))))))))
(ROOT (S (VP (VBG ) (SBAR (S (NP (PRP )) (VP (VBD ) (NP (RB ) (NN ))))))))