(S (S (BASENP (DT Both) (NNS events)) (VP (VBD occurred) (PP (IN on) (NP (BASENP (NNP Boeing) (NNP 777-200ER) (NNS airplanes)) (VP (VBN powered) (PP (IN by) (BASENP (NNP Rolls-Royce) (NNP RB211) (NNP Trent) (NNP 800) (NNP Series) (NNS engines)))))))) (PERIOD .))