(S (S (BASENP (DT The) (NN wreck)) (VP (VBD caused) (NP (BASENP (DT a) (JJ massive) (NN fire)) (SBAR (WHNP (WDT that)) (S (VP (VBD burned) (PP (IN for) (BASENP (QP (RB over) (NN six)) (NNS hours))))))))) (PERIOD .))