Date published November 5, 2014 by Shane Bryson. Date updated: September 17, 2015
If argumentative essays were newspaper articles, thesis statements would be the headlines—and as a thesis statement is like the headline of an essay, a topic sentence is like the headline of a paragraph. This is because, like the thesis, they let the reader know what to expect.
Topic sentences have three basic functions:
- Describe all and only the topic matter of the paragraph.
- Clearly situate the paragraph’s content in relation to the thesis.
- Provide a transition from the preceding paragraph.
View topic sentences in an example essay
1. How much topic matter to cover with a topic sentence
All and only
Though small, the words “all” and “only” are both very important here. The first requires your topic sentence to cover enough information, while the second limits the amount of information the topic sentence should cover.
All of the information in the paragraph should relate clearly to the topic sentence. This means, reciprocally, that the topic sentence should be just broad enough to account for, with some detail, all the points you make in the paragraph. Make sure the topic sentence is sufficiently expansive and precise. To help with this, use key words from the most important point(s) you make in the body of the paragraph.
However, only the information in the paragraph should be covered by the topic sentence (except in the case of compound topic sentences). This means that the topic sentence should not be any broader than the topic matter in the paragraph requires.
Thinking of these all and only requirements, consider your topic sentence to present a miniature mirror-image of the paragraph’s content. Everything you see in the paragraph you should also see in the topic sentence; on the other hand, usually, information that you don’t see in the paragraph you should not see in the topic sentence.
When revising your paragraphs, if you notice a difference between what the topic sentence covers and what the paragraph covers, you always have two options: change the topic sentence or change the paragraph. Perhaps you will need to carefully add a few words to the topic sentence; or perhaps something important is missing from the paragraph, and you will need to add that. On the other hand, perhaps your topic sentence is too broad, and you need to cut something from it; or perhaps your paragraph covers information irrelevant to the topic sentence, and you need to delete that information or find it a new home.
Compound topic sentences
Sometimes a topic sentence works more like a section introduction, outlining information that will come over the next two or three paragraphs. In this case, you should use two topic sentences in the same paragraph, what we might call a compound topic sentence. The first of the two is the section-heading-like topic sentence—the same “all and only” rules apply to this topic sentence, but it covers a few paragraphs’ worth of information. The second topic sentence picks up one part of the first and covers all and only the information in the present paragraph.
Example Compound Topic Sentence
[First T.S.] The government has three main obstacles to developing tidal hydro power on the coast: funding, location, and technological innovation. [Second T.S.] The problem of funding results from prior financial commitments and the relatively low budget of the province.
The present paragraph would continue to discuss funding, while the next paragraph would take up location, starting with another topic sentence.
2. Connection to the thesis or overall argument
Covering only the first basic function, the topic sentence is incomplete. We might know what the paragraph is about, but we need to know why this information is important to the main point of the essay. The second function of the topic sentence clarifies this matter—connect the topic sentence to the thesis.
To ensure that your topic sentences fulfill this second function, ask yourself, “How does this paragraph help the reader understand why my thesis is right? How can the reader identify the connection between the point I make here and the overall point that I earlier set out to make?” Answers to these questions should be obvious from the topic sentence.
To help ensure these connections are clear, re-use key words that you’ve used in your thesis, and make sure that you are explicit about how the paragraph explores the larger point. To illustrate, for the compound topic sentence we considered a moment ago, consider the following thesis:
Example Thesis Statement
Efforts from NGO’s and the government to establish tidal hydro power in Nova Scotia face many obstacles, but by working together the two groups can meet with success by 2020.
Our compound topic sentence establishes the connection to the parts of this thesis by specifically mentioning “the government” and “obstacles,” so that the reader knows what part of the thesis the associated paragraphs will explore, and by giving some further detail, so that the reader better understands what nuances of the paper will pick out.
As we saw with compound topic sentences, the topic sentence for a paragraph does not always need to relate directly to the thesis. For example, the topic sentences that follow a compound topic sentence refer to the compound topic sentence, but it refers to the thesis. Similarly, in longer essays that use subsections, topic sentences can refer to the main point laid out in the subsection’s introduction.
What’s important here is that the topic sentence either connects to the thesis or connects to something else, which in turn connects with the thesis.
Being the sentence that encapsulates the paragraph, a topic sentence often provides an ideal place to transition from the topic matter of the previous paragraph or section to the topic matter of the present paragraph or section. Transitioning is really an optional function of the topic sentence, but if the transition does not appear in the topic sentence, normally it should appear be just before the topic sentence.
There are actually two types of topic sentences for essays.
- There is, of course, the main essay topic sentence which is often called the thesis statement. It makes the point of the essay clear to the reader and appears in the introduction.
- There are then the good topic sentences for essays that introduce each paragraph.
Creating both of these types of essay topic sentences will take different approaches.
How to Write a Topic Sentence for an Essay
Whether you call it a thesis statement or a topic sentence for essay pieces you write, there is a process you can use to get one that is solid.
Begin by asking some questions:
- What question is my paper exploring or answering?
- What is the main point I am going to make about this topic?
Now you must narrow your question/point to fit the length of the assignment. If, for example, your general topic is obesity in the United States, you may need to focus on one aspect of that huge and complex issue. Are you interested in its causes? Are you interested in the impact of it on the cost of health care? Are you interested in prevention or treatment strategies? Once you have narrowed your question, you are ready to develop a topic sentence for an essay on obesity. Such a topic sentence (thesis statement) might be: “The medical costs of obesity in the U.S. have now reached $150 billion annually, and we must develop strategies to prevent and treat it.”
So, if you want to know how to make a topic sentence for an essay, begin by asking yourself the right question and then narrow that question to meet the length requirements.
How to Make Topic Sentences for an Essay
Now, you have your topic sentence for an essay. You will follow the normal process for producing that essay, including research, an outline, and the rough and final drafts.
As you write your essay, there will be paragraphs that will have topic sentences in essays that must be written.
Each paragraph has a main idea, a main point, just as there is a topic sentence of an essay in total. That main point is stated for the reader in a topic sentence and the followed by detail that all relates to that sentence.
Ask yourself the same questions. What is this paragraph about? What is the point being made? The answers will give you a topic sentence in essay paragraphs.
Topic Sentence for Argumentative Essay
Argumentative essays are special. When you have to write this type of essay or paper, your opinion must be included in the argumentative essay topic sentence. Here’s a brief example.
Suppose you have a very strong opinion about student loan debt. But you are not sure how to write a topic sentence for an argumentative essay on the topic. You do know that it should be included in your introductory paragraph. You might begin that introduction with some startling statistic. For example: “Student loan debt has now reached $1.4 billion and is having a major impact on the US. economy. This translates to about $38,000 per student, and these grads are delaying making major purchases (homes and cars) because of their debt repayment obligations.”
You have now introduced the topic of your essay. But this is not the topic sentence of an essay that puts forth an argument. Your opinion on this topic is what will be the thesis statement. For example, “Both the federal and state governments must find solutions to this debt crisis by making public colleges/universities free and by providing interest-free loans to those who must borrow.” Now you have a solid topic sentence in an essay that poses an argument.
Likewise, paragraph topic sentences for argumentative essays must each include an opinion. “Making public colleges free to students will ensure that all young people will have the opportunity to go to college if they wish.”
The What and the How
You now understand what is a topic sentence in an essay. What is more difficult is how to write an essay topic sentence. Perhaps the example above has helped.
Don’t struggle needlessly over thesis and topic sentences, especially if you are facing a short deadline. Get some help from a reputable essay writing service. And, if you are not sure what are the best paper writing services, check out some of the review sites on them. You will find those that are most highly recommended.
The topic sentence in an essay is critical. Make sure yours is as solid as it can be.