(S (S (S (NP (BASENP (DT The) (NN price)) (PP (IN for) (NP (BASENP (DT a) (NN barrel)) (PP (IN of) (BASENP (NN oil)))))) (VP (VBD dropped))) (SBAR (IN after) (S (BASENP (NN news)) (VP (VBD broke) (SBAR (IN that) (S (NP (NP (NP (BASENP (NNP Al) (NNP Qaeda) (POS 's)) (NN leader)) (PP (IN in) (BASENP (NNP Iraq)))) (BASENP (NNP Abu) (NNP Musab) (NNP al-Zarqawi))) (VP (VBD had) (VP (VBN been) (VP (VP (VBN killed) (PP (IN in) (BASENP (DT a) (NNP US) (NN airstrike)))) (BASENP (NNP Thursday))))))))))) (PERIOD .))