(S (S (BASENP (NNS Critics)) (VP (VBP have) (VP (VBN raised) (NP (BASENP (NNS concerns)) (PP (IN over) (S (BASENP (NNP Sir) (NNP Alan)) (VP (VBG holding) (BASENP (DT both) (NNS roles))))))))) (PERIOD .))