The Lorax introduces the story of ThneedVille, a city in which everything is artificial, even the trees. The residents then sing a song about everything their city has to offer and how much they enjoy living in it.
Jason uses descriptive writing to commemorate a location that was dear to his predecessors with wistful and vivid imagery. In his commemoration, he describes each of his family members in succinct detail.
Raya details the world when it was at peace and how it all changed. She describes the situation with the dragons and how they protected the world. Then something bad came along and put people at odds and split the world. Good for compare/contrast of the world.