(S (S (BASENP (DT The) (NNP Boeing) (NNP 737)) (VP (VP (VBZ has) (NP (BASENP (DT a) (JJ cruising) (NN speed)) (PP (IN of) (NP (BASENP (NN 900) (NNS kilometres)) (PP (IN per) (BASENP (NN hour))))))) (CC and) (VP (VBD was) (VP (VP (VP (VBG flying) (ADVP (RB constantly))) (PP (IN at) (NP (BASENP (DT an) (NN altitude)) (PP (IN of) (BASENP (NN 10,000) (NNS metres)))))) (PP (IN for) (BASENP (NN two) (NNS hours))))))) (PERIOD .))