Topic Sentences

A topic sentence is a sentence that indicates the main idea or thesis of a paragraph. Not all paragraphs have clear-cut topic sentences, and topic sentences can actually occur anywhere in the paragraph (as the first sentence, the last sentence, or somewhere in the middle); however, an easy way to make sure your reader understands the point of each paragraph is to write the topic sentence near the beginning . Regardless of whether you include an explicit topic sentence or not, you should be able to easily summarize what the paragraph is about.

The Purposes of a Topic Sentence

  1. Alert the reader to the topic or main point of the paragraph.
  2. Signify how you will approach the topic or main point of the paragraph.
  3. Support the thesis statement.

Questions to Consider

  1. Pay close attention to the focus of each paragraph.  Are any of your paragraphs too large and complex? Can any of your shorter paragraphs be combined?
  2. Consider why you chose to include each of your paragraphs.  What is the connection between that paragraph and the thesis?  Why are they in this particular sequence?
  3. Make sure you know what you want your reader to understand or believe at the end of reading each paragraph.  How should they interpret the information in that paragraph?

Topic Sentence Check

After you have written your thesis and topic sentences, combine them into a single paragraph.  If this paragraph conveys your argument clearly and completely, then you have strong topic sentences.  This short paragraph can serve as a summary of your argument.

Guidelines for Topic Sentences

  1. A topic sentence must be complete to perform all the necessary functions.

Weak: Some types of birth control should be provided by schools.

Better: To prevent unwanted pregnancies and sexually transmitted diseases, schools should provide every form of non-prescription birth control available.

  1. A topic sentence must predict or promise what follows, so it cannot be a question.

Weak: Should schools provide free computers for their students?

Better: Since schools should assist students in their studies and prepare them for their future careers, they must offer students the technological advantage of free and easy access to computers.

  1. Phrases such as “I think” or “in my opinion” weaken topic sentences. Your writing is always your opinion, so you don’t need these phrases.

Weak: I think that it is important for every woman to carry mace or pepper spray.

Better: As violent criminals take over the city, women must carry mace or pepper spray to protect themselves.

  1. The topic sentence should provide clear relationships among all of its elements so that it can provide a framework for understanding the rest of the paragraph.

Weak: Historians record only dry statistics; we should read novels.

Better: Accurate historical novels give us a deeper understanding of the past than do the dry collection of facts and statistics that pass for history texts.

  1. A topic sentence needs to be clear and specific so it can predict and summarize the rest of the paragraph for the reader.

Weak: Public transit is terrible.

Better: Incapable of providing reliable, comfortable service, the San Francisco Municipal Transit system is failing its ridership.

  1. A topic sentence must be coherent so the reader can use it as a key to the rest of the paragraph.

Weak: The differences of their socioeconomic classes, indeed, were not more potent than the already inherent differences among the population.

Better: Bosnia is split apart not by any economic class differences, but by racial and ethnic conflicts.

Kaylan| 2019

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