Q. What is a topic sentence?

A topic sentence is usually the first sentence of a body paragraph, and it expresses the main idea of that paragraph while also supporting the thesis of the entire essay. To achieve its purpose, a topic sentence should

• have a clear connection back to the thesis; in other words, the reader should understand how it supports the entire essay's point.
• be specific and narrow enough to tackle its idea well in one paragraph.
• match the purpose of the paragraph through how it is phrased. For example, if its paragraph is informative, the topic sentence should state a fact, but if its paragraph is argumentative, the topic sentence should make a persuasive claim.
• encapsulate the content of its paragraph in a single sentence -- anything in its paragraph that does not fit with its idea should be removed, or the topic sentence should be revised.
• begin with a transition of some kind that links it to the idea the previous paragraph ended with. That way, the reader can see how the two ideas connect.

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