(S (S (BASENP (DT The) (NNP Yeltsin) (NN era)) (VP (VBD was) (NP (NP (BASENP (DT a) (JJ traumatic) (NN period)) (PP (IN in) (BASENP (JJ Russian) (NN history)))) (COLON --) (VP (VBN marked) (PP (IN by) (NP (NP (BASENP (JJ widespread) (NN corruption)) (COMMA ,) (BASENP (JJ economic) (NN collapse))) (CONJP (COMMA ,) (CC and)) (BASENP (JJ enormous) (ADJP (JJ political) (CC and) (JJ social)) (NNS problems)))))))) (PERIOD .))