How we cite our quotes: Citations follow this format: (Chapter.Paragraph)
Quote #1
These powers received due admiration from Catherine, to whom they were entirely new, and the respect which they naturally inspired might have been too great for familiarity, had not the easy gaiety of Miss Thorpe's manners [...] softened down every feeling of awe, and left nothing but tender affection. (4.9)
Catherine's feelings of awe towards the older and seemingly wiser Isabella are significant here, as they point to Catherine's tendency towards hero worship.
Quote #2
Perhaps Catherine was wrong in not demanding the cause of that gentle emotion - but she was not experienced enough in the finesse of love, or the duties of friendship, to know when delicate raillery was properly called for, or when a confidence should be forced. (5.2)
Catherine's lack of experience in relationships, as well as her emotional immaturity, creates uncertain situations for her. Words like "duties" and "to know," suggest the ways in which relationships are conducted by certain rules that the young and inexperienced Catherine will need to learn.
Quote #3
[B]ut, where youth and diffidence are united, it requires uncommon steadiness of reason to resist the attraction of being called the most charming girl in the world. (7.44)
Catherine's youth helps to make her gullible, or easily trusting. She is at least partially swayed by John's compliments, even as she finds him increasingly annoying.