Here's why:
* Unity in writing means that all parts of a sentence, paragraph, or essay work together to support a single main idea.
* When a sentence includes unrelated ideas, it becomes confusing and difficult to follow. The reader is left wondering how the different parts of the sentence connect.
For example:
* Ununified: "The cat chased the mouse, and the sky is blue." (These two ideas have no connection.)
* Unified: "The cat chased the mouse across the kitchen floor, its sharp claws clicking on the linoleum." (All elements of the sentence contribute to the idea of the cat chasing the mouse.)