Paragraph Development

  • Unity
  • Coherence
  • Adequate Development
  • Topic Sentences

    A paragraph is a collection of sentences which all relate to one main idea or topic. Effective paragraphs have four main characteristics: a topic sentence, unity, coherence, and adequate development. Each of these characteristics is discussed below.


    Unity refers to the extent to which all of the ideas contained within a given paragraph "hang together" in a way that is easy for the reader to understand. When the writer changes to a new idea -- one which is not consistent with the topic sentence of the paragraph -- the writer should begin a new paragraph. Unity is important because it aids the reader in following along with the writer's ideas. The reader can expect that a given paragraph will deal only with one main topic; when a new paragraph begins, this signals that the writer is moving on to a new topic.

    Consider the following example. Note that there are two main ideas presented in this paragraph. The topic sentence indicates that the paragraph will deal with the subject of "employees' attitudes," but the paragraph shifts unexpectedly to the topic of "management's attitudes." To achieve unity in this paragraph, the writer should begin a new paragraph when the switch is made from employees to managers.


    "Employees' attitudes at Jonstone Electric Company should be improved. The workers do not feel that they are a working team instead of just individuals. If people felt they were a part of a team, they would not misuse the tools, or deliberately undermine the work of others. Management's attitude toward its employees should also be improved. Managers at Jonstone Electric act as though their employees are incapable of making decisions or doing their own work. Managers treat workers like objects, not human beings."


    Coherence refers to the extent to which the flow of ideas in a paragraph is easily understood by the reader. For this reason, coherence is closely related to unity. When a writer changes main ideas or topics within a paragraph, confusion often results. To achieve coherence, then, a writer should show how all of the ideas contained in a paragraph are relevant to the main topic.

    Consider the example below. In this paragraph, the writer begins with the topic of job-skills courses, but veers off onto the topic of algebra and history before returning to the subject of courses on employment. As a result, the paragraph is disjointed and difficult to understand.


    "Schools should offer courses to help students with the problems of unemployment. Such a course might begin with a discussion of where to find employment, then cover resume writing and interviewing. Algebra and history don't help students with real-world needs. They are required courses that students aren't interested in, and this is frustrating for students who would rather learn about other subjects. If schools offered job-skills courses, students would be well prepared for the difficult task of finding a job once they finish school."

    Adequate Development

    A paragraph is adequately developed when it describes, explains and supports the topic sentence. If the "promise" of the topic sentence is not fulfilled, or if the reader is left with questions after reading the paragraph, the paragraph has not been adequately developed. Generally speaking, a paragraph which consists of only two or three sentences is under-developed. A good rule of thumb to follow is to make sure that a paragraph contains at least four sentences which explain and elaborate on the topic sentence.

    Consider the paragraph below. The topic sentence promises to discuss "several" points of comparison and contrast between leadership and management, but the remainder of the paragraph falls short of fulfilling this promise. Only one point of comparison is raised, and this point is left unexplained. Several questions remain unanswered. How are leaders different from managers? In what specific ways are the two alike? Why must a manager be a good leader to be effective? Why must good leaders know how to manage people effectively? To achieve adequate development in this paragraph, these questions should be addressed.


    "The topics of leadership and management are both similar to and different from one another in several important ways. To be effective, a manager should be a good leader. And good leaders know how to manage people effectively."

    Generally speaking, a paragraph should contain between three and five sentences, all of which help clarify and support the main idea of the paragraph. When a writer begins a new paragraph, it signals to the reader that the writer is changing thoughts or ideas, or is moving on to discuss a different aspect of a main idea.

    Topic Sentences

    Beginning a paragraph with a topic sentence is one of the best ways to achieve clarity and unity in one's writing. The function of a topic sentence is to describe what the paragraph will be about, such that the reader has clear expectations about what will follow. An effective topic sentence typically contains only one main idea. The remainder of the paragraph then develops that idea more fully, offering supporting points and examples. After reading a topic sentence, one should be able to anticipate the type of information contained in the rest of the paragraph. If the remainder of the paragraph does not fulfill the "promise" of the topic sentence, the paragraph will lack unity, coherence and adequate development.


    "The cockroaches that inhabit many city apartments and homes are parasites that are almost impossible to exterminate completely."

    Notice that this sentence clearly identifies that the key topic of the paragraph is cockroaches. It also indicates what the remainder of the paragraph will discuss: the difficulty of exterminating cockroaches. The reader can then expect the rest of the paragraph to explain how and why cockroaches are difficult to eliminate.

    "Many television cartoons contain an unhealthy amount of violence."

    Notice that this sentence clearly identifies that the key topic of the paragraph is violence in television cartoons. It also indicates that the remainder of the paragraph will discuss how much violence cartoons typically contain, and how/why this violence is unhealthy for viewers.

    "An increasing number of people in America are enjoying the benefits of organically grown fruits and vegetables."

    This topic sentence indicates that the remainder of the paragraph will cover the trend in the United States toward eating organic foods. The reader can also anticipate learning more in this paragraph about the specific benefits of organic foods.