(QT (DQL ``) (QTC (S (BASENP (DT The) (NN puzzle)) (VP (VBZ is) (SBAR (WHADVP (WRB how)) (S (BASENP (DT the) (NN moon)) (VP (VBD developed) (BASENP (DT a) (JJ warm) (NN core))))))) (PERIOD .)) (DQR ''))