(S (S (NP (BASENP (NNS Authorities)) (PP (IN from) (BASENP (DT the) (NNP Occupational) (NNP Safety) (CC and) (NNP Health) (NNP Administration)))) (VP (VP (VBP do) (RB not)) (VP (VB know) (SBAR (WHADVP (WRB why)) (S (BASENP (DT the) (NN platform)) (VP (VP (VBD broke) (ADJP (JJ free))) (PP (IN from) (BASENP (DT the) (NN bridge))))))))) (PERIOD .))