(S (S (QT (DQL ``) (QTC (S (BASENP (PRP We)) (VP (VBP 've) (VP (VP (VBN seen) (NP (BASENP (DT a) (JJ marked) (NN decrease)) (PP (IN in) (NP (BASENP (DT the) (NN frequency)) (PP (IN of) (BASENP (NN frost))))))) (COMMA ,) (PP (ADVP (RB especially)) (PP (IN in) (BASENP (JJ inland) (NNP Queensland))))))) (COMMA ,)) (DQR '')) (S (BASENP (NNP Dr) (NNP Trewin)) (VP (VBD said)))) (PERIOD .))