(S (S (NP (BASENP (DT A) (NN witness)) (ADVP (RB there))) (VP (VBD said) (SBAR (S (BASENP (DT a) (NN man)) (VP (VP (VBD dropped) (BASENP (DT a) (NN grenade))) (PP (IN from) (BASENP (DT a) (NN pedestrian) (NN bridge)))))))) (PERIOD .))