The setting can help a reader understand the theme.
This one is actually a good question. Well first, this is from the great gatsby. Fitzgerald was trying to give a balance view in the beginning of who the great gatsby was. And even the author, he lived a wonderful life that is why he related that into Caraway's character, having the same background as him.
D a frame is to a picture
I want to say it’s Ethos but I’m not 100% sure!
