(S (S (BASENP (NNS Witnesses)) (VP (VBD said) (SBAR (S (BASENP (NNP Mr.) (NNP Stewart)) (VP (VBD appeared) (S (VP (TO to) (VP (VP (VB lose) (NP (BASENP (NN control)) (PP (IN of) (BASENP (DT the) (NN truck))))) (PP (IN after) (S (VP (VP (VBG entering) (NP (BASENP (DT a) (NN curve)) (PP (IN in) (BASENP (DT the) (NN road))))) (PP (IN at) (NP (BASENP (DT a) (JJ high) (NN rate)) (PP (IN of) (BASENP (NN speed)))))))))))))))) (PERIOD .))