A paragraph is the unit which contains a collection of words which has a singular idea in them that is used to narrate an event, or a main idea in a piece of writing.
With this in mind, we can see that there is a need for the paragraphs to act as either a means of narration or to show details which would help a reader to reach a conclusion.
For example, if a paragraph is talking about the effect of pollution, he is trying to reach the conclusion that pollution is bad and should be minimized as much as possible.
