How to Write a Solid Thesis Statement

The important sentence expresses your central assertion or argument

A male student studying in the library.
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A thesis statement provides the foundation for your entire research paper or essay. This statement is the central assertion that you want to express in your essay.

Put another way, a thesis statement is a one-sentence, or occasionally a two-sentence, statement of your central idea, say Diane Hacker and Nancy Sommers in "A Pocket Style Manual," adding: "The thesis (statement) expresses your informed, reasoned answer to your research question — an answer about which people might disagree."

Usually, the thesis statement will appear at the end of the first paragraph of your paper. Knowing the definition of a thesis statement is only part of the equation: There are a few different types, and the content of your thesis statement will depend upon the type of paper you’re writing.

Types of Theses Statements

Before creating a thesis statement, it's important to ask a few basic questions, which will help you determine the kind of essay or paper you plan to create:

  • Are you defending a stance in a controversial essay?
  • Are you simply giving an overview or describing an event, object, or process?
  • Are you conducting an analysis of an event, object, or process?

In every thesis statement, you will give the reader a preview of your paper's content, but the message will differ a little depending on the essay type.


If you have been instructed to take a stance on one side of a controversial issue, you will need to write an argument essay. Your thesis statement should express the stance you are taking and may give the reader a preview or a hint of your evidence. The thesis of an argument essay could look something like the following:

  • When students are exposed to graphic documentaries that show the dangers of texting and driving, they become more responsible drivers.
  • The practice of hydraulic fracturing to access natural gas can lead to dangerous manmade earthquakes.
  • The popular practice of leashing a child can lead to risky behavior in adolescence.
  • Street cameras and street-view maps have led to a total loss of privacy in the United States.

These thesis statements are effective because they offer opinions that can be supported by evidence. If you are writing an argument essay, you can craft your own thesis around the structure of the statements above.

Expository Essay

An expository essay "exposes" the reader to a new topic; it informs the reader with details, descriptions, or explanations of a subject. If you are writing an expository essay, your thesis statement should explain to the reader what she will learn in your essay. For example:

  • Eggs contain many of the ingredients that your body needs for good health.
  • The rewarding process of photographing a lunar eclipse requires careful preparation and sound equipment.
  • The Mesa Verde National Park reveals the fascinating culture of the Ancestral Puebloans who lived on the land for more than 700 years.
  • The Spanish Inquisition is characterized by the religious persecution that was often carried out with extreme cruelty.

These statements provide a statement of fact about the topic (not just opinion) but leave the door open for you to elaborate with plenty of details. As Sarah Montante notes in her article, "Crafting a Thesis for an Expository Essay," published on "You do not have to develop an argument or prove anything in an expository essay; you only have to understand your topic and present it to the reader in a logical, cogent manner." A good thesis statement in an expository essay always leaves the reader wanting more details.

Analytical Essay

In an analytical essay assignment, you will be expected to break down a topic, process, or object in order to observe and analyze your subject piece by piece. Examples of a thesis statement for an analytical essay include:

  • A careful examination of the way that our fat cells store and release calories will shed light on the difficulties of losing weight.
  • Ultimately, the crime scene yielded sufficient evidence for solving the crime, but the clues were only discovered after a meticulous investigation.
  • It is easy to see why school mornings are so chaotic when you examine every task we try to accomplish in this short amount of time.

Because the role of the thesis statement is to state the central message of your entire paper, it is important to revisit (and maybe rewrite) your thesis statement after the paper is written. In fact, it is quite normal for your message to change as you construct your paper.