A paragraph is a collection of sentences about a single idea. It is important to stay focused on that idea throughout the paragraph. If the paragraph is part of a larger article, story or report, it should fit logically into the flow of the paragraphs before and after it. A short paragraph might be only two or three sentences long. Paragraph length, however, is relative to the surrounding paragraphs. If your document contains much longer paragraphs, a paragraph of five or six sentences might be considered short.

Identify the main idea of your paragraph. If you choose a broad topic for the main idea, you probably won't have room in a short paragraph to cover everything related to that main idea. You can use a short paragraph as an introduction to a broad topic, however. For example, if your paragraph will be about the benefits of exercise, you may be able to list several benefits, but you won't have room to provide details about all of them in a short paragraph. If you narrow your focus to write about just one of the benefits of exercise, you can use the rest of the paragraph to provide details about that particular benefit.

Research information that supports the main idea of the paragraph. Consider statistics, series of events, examples, definitions, advantages, disadvantages and related ideas. In a short paragraph, you will need to limit your supporting information to a few sentences. Select the strongest pieces of supporting information to support your main idea.

Write a topic sentence summarizing the main idea of the paragraph. This is usually the first sentence of a paragraph and it sets the course for the rest of the paragraph. By reading the topic sentence, the reader knows that the rest of the paragraph will provide more information related to the main idea. For example: "One benefit of exercise is that it burns calories." This lets the reader know that the following sentences in the paragraph will provide more information about this benefit.

Write sentences supporting the topic sentence using the information you gathered in your research. Choose the information that provides the strongest support for your topic sentence. For example, you might include a sentence with a statistic from an expert about the number of calories used during a half-hour walk. You might follow this with a sentence about the effect of burning calories on the person's health.

Use complete sentences and proper grammar when writing a short paragraph. Review what you have written for clarity. If you think your supporting sentences do not contain enough information to support the topic sentence, consider adding more sentences or narrowing the focus of your topic sentence.