(S (S (BASENP (DT The) (NN letter)) (VP (VBD came) (PP (IN as) (NP (BASENP (NN part)) (PP (IN of) (NP (NP (BASENP (DT an) (NNP Army) (NN investigation)) (PP (IN since) (BASENP (NNP November)))) (VP (VBG regarding) (NP (BASENP (NN violation)) (PP (IN of) (BASENP (DT the) (NN contract))))))))))) (PERIOD .))