Definition

Noun: A sentence, typically the first sentence in a paragraph, that expresses the main idea or central point which the rest of the paragraph will develop, explain, or support.

Usage

The topic sentence is a fundamental element of paragraph structure in academic and formal writing. It serves as a guide for the reader, clearly stating what the paragraph will be about. A strong topic sentence is usually specific, debatable, and focused enough to be fully discussed within a single paragraph.

Examples

• A good topic sentence clearly introduces the paragraph's main argument.
• The writer struggled to formulate a strong topic sentence for the concluding paragraph.
• In the essay, each topic sentence directly supported the thesis statement.
• The professor circled the topic sentence and wrote "vague" in the margin.

Advanced Usage

• Implied Topic Sentence: In some narrative or descriptive writing, the main idea of a paragraph may be implied rather than stated in a single, explicit topic sentence. However, in expository and argumentative writing, an explicit topic sentence is standard.
• Positioning: While most commonly the first sentence, a topic sentence can sometimes be placed at the end of a paragraph for dramatic effect or in the middle as a transitional pivot between ideas.

Variants and Related Words

• Thesis Statement: A sentence that states the main argument of an entire essay or paper, to which all topic sentences should relate.
• Controlling Idea: The specific focus or claim within a topic sentence that the paragraph will control or prove.

Synonyms

• Main idea sentence
• Paragraph leader
• Lead sentence (in the context of paragraph structure)

Related Phrases

• To have a clear topic sentence: To write a paragraph that is unified and easy to follow because its main point is explicitly stated.
  • Example: Your analysis would be stronger if each paragraph had a clear topic sentence.
• To support the topic sentence: To provide evidence, examples, and analysis within a paragraph that directly relate to and prove the claim made in the topic sentence.
  • Example: The following three sentences effectively support the topic sentence with data from the study.

Noun

1. a sentence that states the topic of its paragraph