When writing essays, the essay and its paragraphs must be constructed in a way that readers can follow the writer's train of thought. The paragraphs should be moderately short and, like the essay, should begin with a sentence announcing the topic, followed by the supporting arguments. The essay is launched by a thesis statement, whereas focus sentences, also known as topic sentences, open the paragraphs.
Focus Sentence Defined
Thesis sentences announce the topic for the entire essay, with the paragraphs supplying the supportive arguments. The focus sentence -- or topic sentence -- states the main point of each paragraph. It reveals what argument each paragraph will be discussing.
Purpose of a Focus Sentence
The main purpose of a focus sentence is to summarize the information contained within a paragraph. However, it serves several other purposes as well. Focus sentences tie the paragraph to the title, the introductory paragraph and the main topic of the essay. In addition to introducing the paragraph's topic, they hint at the paragraph's supporting information as well as the paragraphs that follow. Focus statements not only state the paragraph's argument and indicate its content, they dictate the sentence arrangement and unify the paragraph contents to the essay as a whole.
Paragraphs Support the Focus Sentence
Although the topic sentence may surface part way into the paragraph on occasion, it usually appears at the beginning to indicate what the paragraph will discuss. The paragraphs discuss a single topic, define and embellish the terms and features described in the focus sentence, and display the paper's subdivisions -- indicating where each new argument begins. The paragraph's sentences correlate to the focus sentence, and are assembled in an ordered and logical manner. Like the essay itself, the paragraph is broken down into an introduction (the focus statement), the body (controlling facts, ideas, arguments), and the conclusion (closing sentence that summarizes what was discussed).
Writing a Focus Sentence
Writing good focus sentences, like writing thesis statements, requires determining the main idea of each paragraph and stating it in your own words. First, brainstorm ideas and arguments that support the essay topic, producing a few words and phrases as the focus for several paragraphs. Arrange these words or phrases into a simple outline. For instance, the Roman numerals I and V becomes the essay's introduction and conclusion. The numerals II, III, and IV are followed by the topic words or phrases to be discussed in the paragraphs within the body. Once the essay and paragraph topics have been determined, complete the outline with supporting evidence. Use the essay outline to create a focus statement that summarizes and introduces paragraph content and follow it with supporting facts and evidence.