(S (S (BASENP (JJ Pakistani) (NN security) (NNS forces)) (VP (VP (VBD led) (NP (BASENP (DT a) (JJ major) (NN operation)) (PP (IN against) (BASENP (DT the) (NNP Taliban))))) (PP (IN in) (BASENP (DT this) (NN region))))) (PERIOD .))