4 Breaking Down a Text: Finding the Main Ideas

What is a main idea?

A main idea is the focus of a paragraph (or small group of paragraphs); main ideas support central ideas and develop the author’s thesis. In order to fully communicate their thesis (the overall message about the topic) authors build their message point-by-point or paragraph-by-paragraph. Each paragraph in a text offers something new to help readers understand the thesis better.

As a reader, it is important to understand each main idea as part of understanding the text as a whole. If you understand each main idea, or the focus of each paragraph, then you can see how each one helps to support and develop the author’s thesis.

A main idea is the focus of a paragraph (or a small group of paragraphs).

• It is a complete sentence and therefore a complete thought.
• It is the main point that the author is making about a topic in a specific paragraph.
• It answers the question, “What is the main point the author is making about the topic in this specific paragraph?”
• It is a statement, or claim, about the topic (not a question or fact).

Before you try to find the main ideas, be sure to read and annotate the whole text. Use the strategies in the Before You Read (Pre-reading) and When You Read pages.

How can I find the main ideas?

Have you ever looked at a text and wondered, “Why is this so long? Why did the author use so many words when they could have just said what they really wanted to say in a sentence or two?”

If authors can just communicate their thesis and leave it at that, why do they add all those other words? As a reader, think of yourself as an investigator trying to answer that question. For each paragraph, ask yourself what point the author is making in that chunk of words. What new information or perspective about the topic does the author give us in this paragraph? What is the focus of the paragraph? What details did the author give to help support or develop that focus? Why is this point something the author feels it is important for readers to understand?

It may be helpful to start by identifying and marking all of the supporting details in the paragraph, then look closer at any sentences that do not have those specific facts or examples. The supporting details serve to give specifics about the main idea, but a supporting detail will not be the main idea. Use the process of identifying details as a starting point for investigating the main idea.

Remember, each paragraph serves a purpose to help readers understand the thesis. When you are working to find the main idea of a paragraph, sometimes it helps to think about what would be “missing” or less clear if that paragraph wasn’t there at all. The author could have chosen to leave that paragraph out, right? Finding the main idea of a paragraph means you understand the focus of that paragraph and why the author chose to put it there.

Method 1: Find the topic sentence

Sometimes the focus of a paragraph is stated directly and clearly as a single sentence within the paragraph. The sentence stating the main idea is often called a topic sentence. All the other sentences in the paragraph will explain and support the topic sentence.

Main ideas are often found at the beginning of a paragraph. The first sentence often explains the point of the paragraph and serves as a topic sentence. Main ideas are also often found in the concluding sentences of a paragraph. The author may clarify the main idea by summing up the key information in the paragraph to emphasize the point for readers.

While the opening and closing sentences are frequently where we find the topic
sentence, keep in mind that is not always the case. Read carefully to make sure you identify the actual main idea—do not just assume that it is going to be in the same place in every paragraph.

Method 2: Create the topic sentence

Sometimes the focus of a paragraph is not stated directly and clearly as a single sentence within the paragraph. The main idea may be implied instead, which makes it more challenging to identify. However, the author is still working to make a point with the sentences and details they chose to include in that paragraph.

If an author does not include a direct topic sentence, it means they offered plenty of information for the reader to understand the main idea without it. You just need to do a little extra work as an investigator to put together the clues. Implied ideas can be drawn from supporting details such as facts, reasons, or examples that give hints or suggestions about the author’s main focus in the paragraph. These hints will be clues leading you to discover the main idea in the selected text.

To check that you found and understood the main idea, create your own topic sentence for the paragraph. Think of it as a sentence that could be added to the paragraph to make the main idea even more direct and clear for other readers.

How do I know if I found the main idea?

One strategy to check your reading comprehension is to write a short summary of what you read, restating the point of the paragraph in your own words. Try limiting your summary to a single sentence, leaving out any details and just restating the author’s focus in that paragraph. In other words, paraphrase the topic sentence if there is one or create a topic sentence if there isn’t one.

An additional strategy to check your understanding of the main idea is to rephrase your choice of topic sentence as a question, then see if the rest of the paragraph helps to answer that question. If all the sentences in the paragraph explain and support the topic sentence, then you have successfully identified the main idea.