(S (S (S (BASENP (NNP Qantas)) (VP (VBZ has) (VP (VBN replaced) (NP (QP (ADVP (IN at) (JJS least)) (NN 14)) (NNS engines))))) (CONJP (COMMA ,) (CC and)) (S (BASENP (NNS modifications)) (VP (VBP have) (VP (VBN been) (VP (VBN made) (PP (TO to) (NP (BASENP (NNP Trent) (NNPS 900s)) (VP (VBN used) (PP (IN by) (NP (BASENP (NN two) (JJ other) (NNS companies)) (COMMA ,) (BASENP (NNP Lufthansa) (CC and) (NNP Singapore) (NNPS Airlines)))))))))))) (PERIOD .))