(S (S (BASENP (NNP Captain) (NNP Semrau)) (VP (VP (VBD was) (RB not)) (VP (VBN investigated) (PP (IN for) (NP (BASENP (NN two) (NNS months)) (COMMA ,) (SBAR (WHADVP (WRB when)) (S (BASENP (PRPD his) (NNS superiors)) (VP (VBD heard) (PP (IN of) (BASENP (DT the) (JJ alleged) (NN killing))))))))))) (PERIOD .))