Qualities of a Good Paragraph
Unity: The quality of unity demands that every sentence in a paragraph must be relevant to the development of the main idea as contained in the topic sentence. A writer violates the quality of unity if, in the course of writing, he/she includes a sentence that is irrelevant to the central idea.
Coherence: A paragraph is said to be coherent if the sentences in it are logically arranged to achieve the smooth flow of information from beginning to end.
Completeness: The information contained in the paragraph must be complete, so that the reader is not left in doubt about the main points.