How we cite our quotes: Citations follow this format: (Chapter.Paragraph)
Quote #10
Catherine trembled at the emphasis with which he spoke, and sat pale and breathless, in a most humble mood [...] and the General, recovering his politeness as he looked at her, spent the rest of his time in scolding his daughter, for so foolishly hurrying her fair friend, who was absolutely out of breath from haste, when there was not the least occasion for hurry in the world. (21.5-56)
It is interesting that politeness can be lost and then "recovered" here. For the General, politeness is used to conceal certain aspects of his personality and to deceive others into thinking he is something that he is not, even if what he actually is is rude and unpleasant.
Quote #11
But the inexplicability of the General's conduct dwelt much on her thoughts. That he was very particular in his eating, she had, by her own unassisted observation, already discovered; but why he should say one thing so positively, and mean another all the while, was most unaccountable! How were people, at that rate, to be understood? (26.15)
This is one of the best thematic statements in the whole book on how lying gets in the way of communication between people. Catherine doesn't understand how to translate people's meaning, nor does she understand why it is necessary to deliberately lie and expect people to know that the opposite is meant. Lying is actually inefficient.
Quote #12
Thorpe, most happy to be on speaking terms with a man of General Tilney's importance, had been joyfully and proudly communicative [...] his vanity induced him to represent the family as yet more wealthy than his vanity and avarice had made him believe them. With whomsoever he was, or was likely to be connected, his own consequence always required that theirs should be great, and as his intimacy with any acquaintance grew, so regularly grew their fortune. (30.12)
John lies for purely self-serving purposes here. His own pride and vanity cause him to exaggerate everything around him, including the wealth of his friends.