Main Idea, Thesis Statement & Topic Sentence
It is important for a written piece – an essay, for example – to have structure and organization. Structure and organization help a writer clearly communicate ideas and help the reader understand the ideas being communicated. The main idea, thesis statement, and topic sentences all provide structure to an essay. It is important for both readers and writers to understand the roles of each of these in order to maintain clear communication and understanding of ideas.
- Main idea: The concept that is being discussed or analyzed throughout the entire essay.
- Thesis statement: A one-to-two sentence statement that is usually found in the introduction of the essay and explains the main argument of the entire piece. The body paragraphs and conclusion will all connect to and support this statement.
- Topic sentence: A key sentence at the paragraph level that discusses and elaborates on specific points from the thesis statement.
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Difference Between Thesis Statement and Topic Sentence
It is important to be able to differentiate between a thesis statement and a topic sentence. Although they have similar purposes, they have different roles in communicating the ideas of the piece; one gives the main idea for the entire essay and the other the main idea in supporting paragraphs.
The thesis statement summarizes the argument or analysis that will be discussed throughout the entire essay. It is usually one sentence long, and it is usually located in the introduction paragraph. The supporting paragraphs that follow the introduction explain the important points and ideas of the thesis.
A topic sentence is the key sentence in a supporting paragraph that explains particular points of the thesis of the entire work. A topic sentence tells what that particular paragraph is about; it connects the supporting ideas in it to the argument or analysis that is explained in the thesis statement. Topic sentences occur throughout the essay near the beginning of each paragraph and help transition to new supporting ideas.
Main Idea of an Essay
The main idea is the concept being expressed or examined throughout the essay. The main idea is the gist, meaning what it is mostly about; it is what the whole text says about the topic of the essay. The thesis statement, topic sentences, and supporting sentences will all connect to this idea.
How to Write a Main Idea
An effective main idea can be supported by the details, analysis, and arguments found in the essay. To write a main idea statement, consider the general topic and what will specifically be shared about that topic. The main idea narrows the topic from a large general idea to a more specific idea. Then the main idea statement will be written as a statement that explains what will be shared about that idea.
1. Select a general topic: coffee
2. Narrow down the topic to a specific idea: organic coffee options
3. Write a statement that explains what will be shared about this idea: There are many benefits to choosing organic coffee.
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Thesis Statement
A thesis statement, sometimes referred to as the central idea statement, clearly explains the argument or analysis of the main idea. It is important because it helps readers understand what the essay is about. It is one to two sentences, usually located in the introduction paragraph, and explains the argument or analysis that will be discussed throughout the remainder of the essay. The thesis statement will help readers understand the purpose of the essay.
Writing a Thesis Statement
A thesis statement or central idea statement will indirectly state the purpose of the essay. After determining the main idea statement, writers should create a purpose statement. A purpose statement identifies the audience and explains how and why the content will be presented to the audience.
The purpose statement for the organic coffee example could be the following:
To convince readers to drink organic coffee instead of conventional coffee.
The purpose statement will not be included in the essay, but it helps the writer identify in their mind the reason for writing the essay and the argument being presented. The thesis statement can then be created using the purpose statement as a guide. The thesis statement will explain the main argument or analysis of the essay. The thesis statement should include the reasons that will be presented in the essay as well as the counterargument, if there is one.
Using this same organic coffee example, the following thesis statement can be crafted:
Although it may be easier and cheaper to buy conventional coffees, there are many benefits to drinking organic coffee, including health benefits, environmental benefits, and economic benefits.
How Many Sentences Should a Thesis Statement Be?
The thesis statement can be one to two sentences in length. It is critical that the argument or analysis is presented clearly, so clarity is the priority when constructing a thesis statement.
Writers should begin with a working thesis statement. The reason it is called a working thesis statement is that the thesis statement can be revised throughout the writing process to ensure clarity. Writers may begin with a shorter thesis statement, but then discover the statement needs to be revised to include more information, or they could revise it to succinctly communicate the argument. It is important to remember that the statement itself can be revised for clarity.
What is the Main Goal of a Thesis Statement?
The main goal of a thesis statement is to clearly express the argument or analysis that will be discussed throughout the essay. As mentioned, this statement should also include the supporting reasons and the counterargument. These elements can all be found in the organic coffee thesis statement below:
Although it may be easier and cheaper to buy conventional coffees, there are many benefits to drinking organic coffee, including health benefits, environmental benefits, and economic benefits.
- Argument: There are many benefits to drinking organic coffee.
- Supporting Reasons: health benefits, environmental benefits, and economic benefits
- Counterargument: Although it may be easier and cheaper to buy conventional coffees
Depending on the purpose of the essay, a thesis statement could be explanatory or argumentative. The purpose of an explanatory thesis statement and essay would be to explain or inform the audience. An argumentative thesis statement and essay would aim to convince, persuade, or prove.
Topic Sentence
Topic sentences are used to introduce the main ideas in each paragraph. They are usually found near the beginning of each body paragraph, and they connect to and support the reasons that are stated in the thesis statement. Topic sentences occur throughout the essay and help transition to new supporting ideas.
Topic Sentence vs Main Idea
Topic sentences will include the main idea for that particular paragraph, but they do not explain the main idea for the entire essay. Topic sentences for the organic coffee example will include organic coffee, but also explain the new idea that is being presented about organic coffee.
Topic Sentence Ideas
Each body paragraph will contain a topic sentence that connects to the main idea and thesis statement. The thesis statement included supporting ideas that will be discussed throughout the essay. Each of these ideas can be explained further in a body paragraph.
The three supporting ideas (health, environmental, and economic benefits) mentioned in the example thesis statement will be included in the topic sentences of each body paragraph.
Although it may be easier and cheaper to buy conventional coffees, there are many benefits to drinking organic coffee, including health benefits, environmental benefits, and economic benefits.
- Health benefits: Organic coffee provides health benefits to the coffee drinker.
- Environmental benefits: Sustainable growing methods for organic coffee lead to environmental benefits by preserving the health of the soil.
- Economic benefits: Fair Trade organizations are involved in organic coffee production resulting in economic benefits for coffee farmers.
Lesson Summary
The main idea, thesis statement, and topic sentences all provide structure and create clarity within an essay. Each plays a role in clearly communicating ideas to the reader. It is important for writers to understand each statement’s role and how to use each statement in the essay.
- Main idea: The concept that is being discussed throughout the entire essay.
- Thesis statement: One sentence that explains the main argument or analysis of the main idea, as well as the ideas that support the argument or analysis.
- Topic sentence: The first sentence in each body paragraph that discusses the main idea of that paragraph; these all connect to the reasons provided in the thesis statement.
The main idea establishes the general idea for the piece; while the thesis statement explains the purpose and argument that surrounds the general idea. Topic sentences are used throughout the essay to support the thesis statement.