The topic sentence functions two ways: it clearly refers to and supports the essay’s thesis, and it indicates what will follow in the rest of the paragraph. As the unifying sentence for the paragraph, it is the most general sentence, whereas all supporting sentences provide different types of more specific information, such as facts, details, or examples. An effective topic sentence has the following characteristics:
- A topic sentence has a topic and an angle, extracted from the thesis sentence.
Thesis: Although working for the national parks service may be considered by some to be a “summer job,” careers with the national parks offer mobility within the profession, support for continued learning, and satisfaction in knowing that you are contributing to the preservation and health of the country’s resources.
Weak example #1: National Parks in the U.S. were created in 1916 under President Woodrow Wilson and currently offer hundreds of summer job opportunities per year.
Explanation: This sentence sticks with the topic, national parks, but does not offer an angle extracted from the ideas in the thesis. An essay should not have topic sentences and units of support that are not planned for in the thesis.
Stronger example: Workers with the national parks are encouraged and, in many cases, required to maintain current knowledge within their fields, which is offered through on-the-job training, attendance at seminars, and tuition assistance for appropriate college courses.
Explanation: Choose any part of the angle in the thesis to create a topic sentence with its own topic and angle.
Weak example #2: National Parks work has provided me with many benefits.
Explanation: Although the thesis itself deals with benefits, a topic sentence derived from that thesis needs to more carefully extract a specific portion of that that thesis and make a point about that specific portion.
Stronger example: Workers with the national parks are encouraged and, in many cases, required to maintain current knowledge within their fields, which is offered through on-the-job training, attendance at seminars, and tuition assistance for appropriate college courses.
- A topic sentence provides an accurate indication of what will follow in the rest of the paragraph.
Weak example: First, we need a better way to educate students.
Explanation: The claim is vague because it does not provide enough information about what will follow, and it is too broad to be covered effectively in one paragraph or short unit of support.
Stronger example: Creating a national set of standards for math and English education will improve student learning in many states.
Explanation: The sentence replaces the vague phrase “a better way” and leads readers to expect supporting facts and examples as to why standardizing education in these subjects might improve student learning in many states.
- A good topic sentence is the most general sentence in the paragraph and thus does not include supporting details.
Weak example: Salaries should be capped in baseball for many reasons, most importantly so we don’t allow the same team to win year after year.
Explanation: This topic sentence includes a supporting detail that should be included later in the paragraph to back up the main point.
Stronger example: Introducing a salary cap would improve the game of baseball for many reasons.
Explanation: This topic sentence omits the additional supporting detail so that it can be expanded upon later in the paragraph, yet the sentence still makes a claim about salary caps – improvement of the game.
- A good topic sentence is clear and easy to follow.
Weak example: In general, writing an essay, thesis, or other academic or nonacademic document is considerably easier and of much higher quality if you first construct an outline, of which there are many different types.
Explanation: The confusing sentence structure and unnecessary vocabulary bury the main idea, making it difficult for the reader to follow the topic sentence.
Stronger example: Most forms of writing can be improved by first creating an outline.
Explanation: This topic sentence cuts out unnecessary verbiage and simplifies the previous statement, making it easier for the reader to follow. The writer can include examples of what kinds of writing can benefit from outlining in the supporting sentences.