Social stratification is a system that ranks people based on social rank in a hierarchy. Some groups have much more wealth and power, while others are poor and powerless. It is very difficult for someone in a low-class to become part of a higher class, often leaving people depressed at their inability to be something more.
When the large cat repeats the same words 'Better wait till Martin comes' It creates excitement and curosity in the readers mind that who this Martin is? So, the effect that this repetitive words give to the story is that it pushes the story to it's most exciting part.
