(S (S (NP (BASENP (NNP Sinn) (NNP Féin) (POS 's)) (NN proposal)) (VP (VBZ is) (SBAR (IN for) (S (BASENP (DT the) (NN chairpersonship)) (VP (TO to) (VP (VB revolve) (PP (IN between) (NP (BASENP (PRP them)) (CC and) (BASENP (DT the) (NNP Democratic) (NNP Unionist) (NNP Party)))))))))) (PERIOD .))