Throughout the remaining parts of the book, most of the animals keep working harder and harder under the guise that Mr. Jones is going to return if they do not, and that his return would be worse than their current existence. In reality, they are working more diligently to prop Napoleon up as dictator. One by one, the commandments change to help the pigs and other leaders while the lesser animals suffer under even worse oppression than they had experienced under Farmer Jones. All along, the animals assume they are working for a free and independent farm, but the irony is that they are just working towards the pigs becoming more human-like tyrants.
Answer: A good way to answer such a question is to consider the function of animals as characters. For instance, each of the Three Little Pigs expresses a different approach to planning for the future and managing risk, which can lead to an analysis of how each character represents a moral or physical quality. In terms of narration, note the degree to which the narrator lets the characters speak in their own voices and lets the plot play out without editorializing. In terms of structure, consider how critical events shatter the calm (such as getting lost in the woods or encountering an enemy) and lead to a moral once some kind of order (for better or for worse) is restored.