(S (S (PP (IN In) (NP (BASENP (DT a) (NNP September) (NN 2007) (NN speech)) (PP (IN at) (BASENP (NNP Columbia) (NNP University))))) (COMMA ,) (S (BASENP (JJ Iranian) (NN president) (NNP Mahmoud) (NNP Ahmadinejad)) (VP (VBD was) (VP (VP (VBN challenged) (PP (IN by) (BASENP (NNP University) (NNP president) (NNP Lee) (NNP Bollinger)))) (PP (IN for) (NP (BASENP (NNP Iran) (POS 's)) (NP (BASENP (NN treatment)) (PP (IN of) (BASENP (NNS gays)))))))))) (PERIOD .))