The main idea of a passage is the most important message presented by the author. In a well-written paragraph, most of the sentences support, describe or explain the main idea of that paragraph. The main idea is sometimes stated at the beginning or the end of the paragraph. Sometimes it is only implied.
The main idea of a passage or reading is the central thought or message. In contrast to the term topic, which refers to the subject under discussion, the term main idea refers to the point or thought being expressed. The difference between a topic and a main idea will become clearer to you if you imagine yourself overhearing a conversation in which your name is repeatedly mentioned. When you ask your friends what they were discussing, they say they were talking about you. At that point, you have the topic but not the main idea. Undoubtedly, you wouldn’t be
satisfied until you learned what your friends were saying about this particular topic. You would probably pester them until you knew the main idea, until you knew, that is, exactly what they were saying about your personality, appearance, or behavior. The same principle applies to reading. The topic is seldom enough. You also need to discover the main idea.
When you read for enjoyment or to obtain general information, it is probably not important to remember all the details of a passage. Instead, you want to quickly discover the writer's general message ---- the main idea of the passage. When you read textbooks or articles in your own field, you need both to determine the author's main ideas and to understand the way he develops them. A good way to increase your understanding of this kind of passage is to read it once quickly to find the author's main ideas and then to read it again looking for the details used to support them. We always call this way scanning and skimming.
WHERE ARE MAIN IDEAS FOUND?
It is easy to identify a main idea that is directly expressed in the text.
o Main ideas are often found at the beginning of paragraphs. The first
sentence often explains the subject being discussed in the passage.
o Main ideas are also found in the concluding sentences of a paragraph.
The main idea can be expressed as a summation of the information
in the paragraph as well as a link to the information in the next
The main idea is not always clearly stated. It is more difficult to identify a main
idea when it is inferred or implied. It can be implied through other words in the
paragraph. An implied main idea can be found in several ways.
o Several sentences in a paragraph can imply the main idea by
introducing facts about the topic before actually stating the topic.
o Implied ideas can be drawn from facts, reasons, or examples that
give hints or suggestions concerning the main idea. These hints will
be clues leading you to discover the main idea in the selected text.
o Try the passage below to see if you can pick out the main idea.
Use the hints below to determine the correct main idea of this paragraph.
o After reading a paragraph ask, "What point is the author making in
o Ask the following questions:
Who - Does this passage discuss a person or group of people?
When - Does the information contain a reference to time?
Where - Does the text name a place?
Why - Do you find a reason or explanation for something that
How - Does this information indicate a method or a theory?
HOW CAN I DETERMINE IF I HAVE SELECTED THE CORRECT
MAIN IDEA OF A PARAGRAPH?
If you are able to summarize the information in the passage in your own words, you have absorbed the correct main idea. To accomplish this goal, try the steps
listed below after reading a short section of your textbook.
o Write a short summary in your own words about what you have read.
o Does your summary agree with this general topic?
o Does your summary contain the same ideas being expressed by the
o Could you write a headline (or textbook subheading) that would
express your summary in less than five words?
If you are able to rephrase your choice of a topic sentence into a question and then determine if the passage answers your question, you have been successful at selecting a main idea.
1. As soon as you can define the topic, ask yourself what general point does the author want to make about this topic? Once you can answer that question, you have more than likely found the main idea.
2. Most main ideas are stated or suggested early on in a reading; pay special attention to the first third of any passage, article, or chapter. That’s where you are
likely to get the best statement or clearest expression of the main idea. 3. Pay attention to any idea that is repeated in different ways. If an author
returns to the same thought in several different sentences or paragraphs, that idea is the main or central thought under discussion.
4. Once you feel sure you have found the main idea, test it. Ask yourself if the examples, reasons, statistics, studies, and facts included in the reading lend themselves as evidence or explanation in support of the main idea you have in mind. If they do, your comprehension is right on target. If they don’t, you might want to
revise your first notion about the author’s main idea.
5. The main idea of a passage can be expressed any number of ways. For example, you and your roommate might come up with the same main idea for a reading, but the language in which that idea is expressed would probably be different. When, however, you are asked to find the topic sentence, you are being
asked to find the statement that expresses the main idea in the author’s words. Any
number of people can come up with the main idea for a passage, but only the author of the passage can create the topic sentence.
6. If you are taking a test that asks you to find the thesis or theme of a reading,
don’t let the terms confuse you, you are still looking for the main idea.