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

The function of a topic sentence in a paragraph is to introduce the main idea. It serves as a guide for the reader, indicating what the paragraph will be about. A well-crafted topic sentence not only presents the central theme but also sets the tone and context for the supporting details that follow. It can effectively organize the paragraph and help the reader understand the writer's intent without needing to read the entire section.

A strong topic sentence directly informs the audience of the subject being discussed, fostering clarity and coherence in the writing. It establishes a foundation for the subsequent sentences, which typically elaborate on and support the major idea introduced in the topic sentence. This structure is essential for effective communication, whether in literary works or nonfiction writing.