Paragraph is a group of sentences dealing with on topic. You learned many years ago to recognize paragraph because the first line is indented a few spaces from the left margin. Indentation is the visual signal that a new idea is about to be discussed. A well-written paragraph also has three internal characteristics: unity, coherence, and development.
Unity means that only one idea is discussed in the paragraph.
Coherence means that the sentences are arranged logically and are connected by the use of transitions, pronouns, and the repetition of important words.
Development means that enough specific information is given so that the idea is completely understandable.
There are different kinds of paragraphs, but most that you will write in school are called expository paragraphs. The root word from which the adjective expository is formed is expose, so expository writing exposes, or makes clear and explains. You, then, will be asked to write an idea about a topic (a topic
sentence) and then to explain your idea. The other sentences in the paragraph (illustration sentences) will give details to help readers understand the main idea. Because writers must use enough details to develop an idea, expository paragraphs are usually several sentences long.
The TRI Paragraph
Pattern is a model or plan you use to build or put something together. If you sew, for example, you may use a sewing pattern, cutting your material according to outlines and sewing the material together according instructions. Although there are many ways to develop an idea, one way is to follow a pattern in a paragraph call Topic-Restriction-Illustration, or TRI.
The topic of TRI is a sentence that states the topic, or the main idea, of the paragraph. Restrictions are sentences that limit the topic by making the subject narrower or more focused than it was in the topic sentence. Illustrations are sentences that explain the topic and show something specific about it by-giving examples, including details, presenting facts, or using figures.
The TI Paragraph
Not all paragraphs are built according to the topic-restriction-illustration plan. One way to change the pattern is to begin with a topic sentence and then follow immediately with illustration sentences.
Using Examples to Develop Paragraphs
Illustration sentences, as you have learned, are used to explain the topic. One kind of illustration is the example. An example is one item taken from a larger group or concept. The blue chair in your living room is an example of the furniture in your house. Smog is an example of pollution. The smile on Jim’s face when he receives a bicycle for his birthday is an example of happiness.
Using Facts to Develop Paragraphs
Ideas may be explained in different ways, but readers are more likely to understand your idea if you use facts in your development or illustration sentences. A fact is something that can be proven true. Facts can be checked and verified. It is a fact that John F. Kennedy was the President of the United States from 1961 to 1963. You can verify this fact in many ways. For example, you can talk to people who knew John Kennedy, you can see and hear him on videotape, and you can read about him in books and magazines.