The body paragraphs of an essay, usually argumentative or expository, are the main part of the essay that explain and support the thesis (which is found in the introduction paragraph). It is helpful to give readers a topic sentence because they explain what the paragraph is going to cover and how it ties back to the thesis. The later parts of the paragraph, like the commentary or concrete details, will be used to further explore whatever topic was mentioned in the first sentence of the paragraph. Overall, topic sentences are necessary because they allow the reader to understand the direction of the paragraph, and they organize the essay efficiently.
