(S (S (BASENP (NNP NATO) (NN defense) (NNS ministers)) (VP (VP (VBP are) (PP (IN in) (BASENP (NNP Brussels) (NN meeting)))) (S (VP (TO to) (VP (VB discuss) (NP (BASENP (DT the) (NN controversy) (POS 's)) (BASENP (NN security) (NNS implications)))))))) (PERIOD .))