Jasper’s voice is far more colloquial than Charlie’s. He uses a range of ‘Australianisms’ that Charlie does not have: ‘carn’, ‘fersure’, ‘unnerstand’, ‘nuthin’, ‘somethink’, ‘orright’. Why does Silvey do this?

In my opinion, Silvey uses colloquialism to provide a sense of realism. It also serves to provide insight into Jasper himself... a poor student, who loves sports, but who tends to get into trouble. Being raised by a single father (Jasper's mother is dead), who doesn't pay a lot of attention to him doesn't leave him was an example. Jasper is a product of his environment.