(S (S (BASENP (DT This)) (VP (VBZ is) (NP (BASENP (RB only) (NN one)) (PP (IN in) (NP (BASENP (DT a) (NN series)) (PP (IN of) (NP (BASENP (JJ major) (JJ naval) (NNS drills)) (VP (VP (VBN held) (PP (IN by) (BASENP (NNP Iran)))) (PP (IN in) (NP (BASENP (DT the) (NNP Strait)) (PP (IN of) (BASENP (NNP Hormuz))))))))))))) (PERIOD .))