's because relatively nothing happens . 
(ROOT (S (VP (VBZ 's) (SBAR (IN because) (S (NP (RB relatively) (NN nothing)) (VP (VBZ happens))))) (. .)))
(ROOT (S (VP (VBZ ) (SBAR (IN ) (S (NP (RB ) (NN )) (VP (VBZ ))))) (. )))