(S (S (QT (DQL ``) (QTC (S (S (BASENP (PRP They)) (VP (VBP understand) (SBAR (WHNP (WP what)) (S (S (BASENP (PRP it)) (VP (MD might) (VP (VB mean)))) (SBAR (IN if) (S (BASENP (PRP they)) (VP (VBP do) (RB n't)))))))) (CC and) (S (BASENP (PRP I)) (VP (VBP 'm) (ADJP (JJ confident) (SBAR (IN that) (S (BASENP (PRP they)) (VP (MD will)))))))) (COMMA ,)) (DQR '')) (S (BASENP (NNP Mr) (NNP O'Connor)) (VP (VBD said)))) (PERIOD .))