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Researching and Writing a Paper: Thesis Sentences

This guide is about how to start, research, write, and format, a paper.

Thesis Sentences

Synopsis: "Tell them what you are going to tell them (i.e., your thesis statement), tell them (the body of your paper), tell them what you told them (your conclusion)."

Can you spot the thesis sentence(s) in this paragraph?
A thesis sentence is a single sentence that summarizes the main idea of your topic and declares your position on it. This single sentence (sometimes two, almost never three) is the result of your thinking about the assignment and the information you have found. Before you can create a good thesis statement you need to collect and organize information, look for connections between known facts, and think about the significance of these connections.

Most essays, whether compare/contrast, argumentative, explanatory, or narrative, have thesis statements that take a position and present evidence for that position being true. Unless your essay is simply to inform, your thesis is considered 'persuasive'. A persuasive thesis usually contains an opinion and the reason why your opinion is true. (A good way to write a thesis statement is to consider what is true in the articles, etc., you have read, and then describe how you know it is true. When you can do that in one or two sentences you probably have a good thesis sentence.)

Once you have thought about the information you have found, you will likely have a “working thesis” that has the main idea of your paper and you will also have some thoughts about how to support your thesis statement with evidence. Both how you show the evidence that supports your thesis statement, and the exact wording of your thesis statement, are likely to need to change some as you do more reading and as you write. This is natural and quite common.

  • Length: A thesis statement can be short or long, depending on how many points it mentions. Usually, it is only one relatively short and informative sentence. It contains at least two clauses, usually an independent clause (the opinion, which is usually stated first) and a dependent clause (the reasons for that opinion, usually coming after the opinion). Aim for a single sentence that is maybe two lines long, or maybe about 30 to 40 words long.

  • Position: A thesis statement belongs at the beginning of an essay. It is a sentence that tells the reader what the writer is going to discuss. (Teachers will have different preferences for approximately where the thesis should be, but generally it is in the introduction paragraph, often within the last two or three sentences of that paragraph.)

  • Strength: For a persuasive thesis to be strong, it needs to be arguable. This means that the statement is somewhat not obvious (to people unfamiliar with the articles/books/etc. you have been reading), and it is not something that everyone agrees is true. (The body paragraphs of your paper explain why you are convinced your thesis statement is true.)


Writing a thesis statement takes more thought than many other parts of an essay. But, because a thesis statement summarizes your entire argument in just a few words, it is worth taking the time to compose this sentence as early in your paper-writing as possible. It can help focus your research and how you present your evidence so that your essay is informative, focused, and gives your readers something to think about.

(Do not worry if you discover that you can write a thesis sentence that better summarizes/introduces your paper after you write your conclusion - by the time you 'finish' your paper you have thought a lot more about what you need, or want, to say. So, it is not surprising that you might discover a better way to describe your paper than you had when you started your paper.)

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