(S (S (NP (BASENP (DT The) (NN steel) (NN frame)) (PP (IN of) (NP (NP (BASENP (DT a) (JJ four-storey) (NN building)) (PP (IN under) (BASENP (NN construction)))) (PP (IN in) (BASENP (NNP Vancouver)))))) (VP (VBD collapsed))) (PERIOD .))