In Emma by Jane Austen, what does the first sentence say about how Austen portrays Emma Woodhouse, and which themes are revealed in the first sentence?

In the first sentence of Emma, Austen says that her heroine is beautiful, smart, and wealthy and has a good personality and that she has lived her 21 years without much to disturb her. The first sentence relates to way in which Austen portrays Emma Woodhouse and to the themes of the novel. Emma's life as a young woman in Regency England has led her to be cloistered and naive. Though she is bright, she does not know much about life and must become more enlightened through experience and through connections with men in her life, such as Mr. Knightley, who have been allowed to have more experiences in the outer world. Emma's naiveté leads her to meddle in other people's affairs, such as Harriet's relationships with Mr. Elton and Mr. Martin, in flawed ways. Her lack of experience also causes her to judge other people, such as Jane Fairfax, unfairly. Though her friendship with Mr. Knightley and her experiences with others, Emma is eventually able to cultivate her considerable intelligence and charm into a more worldly approach to life.