We have a privileged view inside the minds of most of the characters, and Austen's strong narratorial voice takes us in and out of the people that populate this novel. Notably, from the very beginning Austen is primarily concerned with showing us the female perspective here – though we occasionally get to see "inside" men, we mostly stick close to the women in the novel, and get to know them better than anyone else.
The main characters of this extract are John Dashwood and his wife Fanny Dashwood.
Fanny Dashwood — the wife of John Dashwood. She is vain, selfish, and snobbish.
Fanny is totally a snob and a half. She basically only wants to associate with people richer or more important than she is. The answer is simple – it's all a matter of money. Happiness and love are secondary to Fanny.
John Dashwood — the son of Henry Dashwood by his first wife. He intends to do well by his half-sisters, but he has a keen sense of avarice, and is easily swayed by his wife. We can't help but feel a little bad for John. On one hand, he's not exactly a good guy; after all, he basically leaves his sisters and stepmother penniless after their father dies. On the other hand, though, he didn't want to do it, and he maybe feels guilty about it – his wife Fanny pressured him into keeping all of the inheritance money. Of course, his wife's not entirely to blame, since he's just as greedy and smarmy as she is.
But in fact they both persuade themselves to be noble, each of them plays their own role, playing up to each other. Maybe even John wants to be persuaded in case not to infringe himself. He runs with the hare and hunt with the hounds. On the one hand he wants to be the father of family but indeed acts as a henpecked husband. So they deserve each other.
As for the language, we should emphasize Austen's novel as a work of satire, her writing is heavily satirical throughout. It’s full of sarcasm, irony and other stylistic devices. There are a lot of exclamations (and as it is-only half blood!-…,five hundred a year!...), rhetorical questions (How could he answer it to himself to rob his child, and his only child too, of so large a sum?, and why was he to ruin himself, and their poor little Harry, by giving away all his money to his half sisters?), graphons (LET, REALLY, THEY, THEM, THAT), polysyndeton (Twice every year these annuities were to be paid; and then there was the trouble of getting it to them; and then one of them was said to have died, and afterwards it turned out to be no such thing.), interplay (convenient addition - prodigious increase). All these devices show the feelings of the main heroes, indicating their emotions to be plausible in their arguments and reasons. Then gradation, which appear through the whole passage, showing how John was more and more sure in Fanny’s words (why, to be sure, to be sure it would, that is very true, undoubtedly, I believe you are right, to be sure it will, I believe you perfectly right, that is a material consideration undoubtedly), exaggerations and so on.
But at the same time no matter how complicated her plots become, or how her characters mystify themselves and each other, Austen's readers are always guided by her strength, consistency, and clarity of style fact.