(S (S (BASENP (NNP Sevior)) (VP (VBZ says) (SBAR (S (NP (BASENP (PRPD his) (NN research)) (PP (IN into) (BASENP (JJ nuclear) (NN waste) (NN disposal)))) (VP (MD should) (VP (VB help) (S (VP (VB dispel) (NP (BASENP (JJ many) (NNS environmentalists) (POS ')) (NNS fears)))))))))) (PERIOD .))