Topic Sentences

Summary

A topic sentence is the first sentence of each paragraph. It should fully capture the one main idea of the paragraph. A reader who reads only the first sentence of each paragraph in your paper should be able to follow the paper’s entire argument.

See below for details and exceptions.

Details

The main idea of the paragraph should be fully captured by the topic sentence.

In an argumentative essay, each topic sentence states an argument or reason. Across the paper, the topic sentences should include all of the reasons needed to support the essay’s thesis statement.

Topic sentences should be at the beginning of each body paragraph unless you have a good reason to place them elsewhere.

Topic sentences are usually just one sentence long, but sometimes two sentences are necessary.

Topic sentences should directly state the main idea of the paragraph.

Scope: the topic sentence must be broad enough to include the full main idea of the paragraph. The topic sentence should not be a claim that is just the first step leading to the main idea.

Topic sentences are usually combined with transitions. They might begin with a transition word or phrase linking the previous paragraph to the current paragraph. Example:

Although Young Woman with a Water Pitcher depicts an unknown middle class woman at an ordinary task, the image is more than realistic because the painter, Vermeer, depicts the subject as strong and regal.

Here, the beginning of the sentence summarizes the previous paragraph and the rest connects the previous idea to the main idea that will be shown in the current paragraph. This sentence thus follows a useful principle for clear writing: always move from old to new information. The subordinate clause (from “although” to “task”) recaps information from the previous paragraph. The independent clauses (starting with “the image” and “the painter”) introduce the new information—a claim about how the image works (“more than realistic’”) and why it works as it does (Vermeer “depicts the subject as strong and regal”).