What is the purpose of a topic sentence in a paragraph?

The purpose of a topic sentence in a paragraph is to introduce the main idea of that paragraph. It serves as a guide for the reader, providing a clear and concise indication of what the paragraph will discuss. This helps to establish the focus for the sentences that follow, allowing the reader to understand the direction of the argument or narrative.

A well-crafted topic sentence sets the tone and context for the supporting details that will elaborate on the main idea. By doing so, it enhances the coherence and structure of the writing, making it easier for the reader to follow along with the writer's thoughts. Supporting details, summaries, and conclusions serve different functions within the paragraph and the overall text, but the topic sentence specifically identifies the central concept that the paragraph addresses.