(S (S (BASENP (NNP Mandela)) (VP (VBZ has) (VP (VBN been) (VP (VP (VBN hospitalised) (BASENP (NN three) (NNS times))) (PP (IN since) (NP (BASENP (DT the) (NN start)) (PP (IN of) (BASENP (JJ last) (NN year))))))))) (PERIOD .))