(S (S (BASENP (NN Liftoff)) (VP (VP (VBD occurred) (PP (IN at) (NP (BASENP (NN 6:00) (NN PM)) (BASENP (NN PDT))))) (COMMA ,) (PP (VBG following) (NP (BASENP (NN two) (JJ previous) (NN launch) (NNS aborts)) (BASENP (DT this) (NN week)))))) (PERIOD .))