IELTS Essentials: The art of smart reading: Spotting main idea

Perennially,  the best way to understand an article is recognizing its main ideas. By understanding the main idea of each paragraph, we are more likely to tackle IELTS reading questions successfully. However, perceiving the main idea may not be easy for some people as they may confuse main ideas with major supporting ideas. In this blog, I will show you the strategy to spot main ideas in IELTS reading passage.

To begin with, I will give you some basic knowledge about a paragraph.

The elements of a reading paragraph

A standard paragraph contains 4 components: Topic, main idea, major supporting details, and minor supporting details.

  • Topic is who or what the paragraph is talking about. We normally find it in the form of one word or phrase, so it’s extremely general.
  • Main idea is what point the author makes about the topic or in the other words:

main idea = topic + writer’s claim

Generally, we can find a main idea as a longer sentence or phrase, therefore, it is more specific than  topic.

  • Major supporting detail is the third elements of a paragraph. Particularly, they are facts, examples, reasons or causes that support the main idea. There will be one more major supporting details in a paragraph.
  • Minor supporting detail is further classification or elaboration of the major supporting detail. This is the optional element of a paragraph.

To help you understand it clearly, Let’s look at the following illustrative example.

” It seems impossible that large prehistoric creatures are alive today. Yet huge creatures from the dinosaur age may still exist beneath the sea. After all, as fossil remains show, dinosaurs had relatives who live in the sea. They were huge and had long necks and snake-like heads.  People who maintain that dinosaurs still live point to recent accounts of strange sea creatures that fit the description of ancient sea monsters.  According to reports, the modern-day sea creatures also have long necks and snake-like heads.”

Now, let’s find the topic, main idea, major supporting details and minor supporting details.

Topic: Dinosaurs that still exist

Main idea (topic sentence): huge creatures from the dinosaur age may still exist beneath the sea

Major supporting details:

(1) dinosaurs had relatives who live in the sea

(2) sea creatures that fit the description of ancient sea monsters

(1) and (2) support the idea that “huge creatures from the dinosaur age may still exist beneath the sea”.

Minor supporting details:

(a) they were huge and had long necks and snake-like heads.

(b) modern-day sea creatures also have long necks and snake-like heads

(a) supports the idea in (1) while (b) endorse the idea in (2)

Main idea in a paragraph

You may expect that the main idea will be stated in the beginning or at the end of a paragraph as in your writing task 2 essay. Unfortunately, life is not always easy and so is the main idea in a paragraph. As you know, a paragraph always has a main idea, otherwise, it’s not a reading paragraph. In particular, you may find a topic sentence anywhere in a paragraph, but the writer often leaves that sentence out when the main idea is so clear. In that case, the main idea is implied and you have to read the whole paragraph to get the idea.

For example, I have a reading extract like this:

“John sings so beautifully that many people think he should be a professional singer. He also won a dance contest last year. Have you ever seen John’s paitings? They are exceptional! In addition, he learned how to program a computer by himself, created an application and made millions of dollars selling it. Sports? John is good at any sport that he has ever played.”

So can you find the main idea using topic sentence in this paragraph? Probably not. In fact, by reading this passage, you may notice that the topic of this paragraph is John and he is talented in many aspects of life such as singing, dancing, painting, programming, and sports. Thus, the main idea could be John is talented in many ways or John is a man of many talents.


Strategy to spot main ideas

Now you knew that a paragraph must have topic, main idea, major supporting ideas and may have minor supporting idea. Additionally, a main idea may appear in anywhere in a paragraph and or it may be implied. Now, I will show you how to identify it within 2 steps.

Step 1: Identifying topic

As main idea is the point that writer make about the topic, so we can only find the main idea once we know the subject matter of the paragraph. An easy way to find topic is based on the frequency it appears in the paragraph. For example, in the above text extract, John is mentioned 7 times under his name and the pronoun ‘he’, so it’s probably the topic which means the text is talking about John. Moreover, to avoid a too broad topic, you should narrow it by asking yourself what aspect of this subject is examined. You could understand this point more in the other examples below.

Step 2: Determining what writer want you to know about the topic

To understand the main idea in a sentence or being implied, you must look for patterns in the details as you read. If you find a sentence that you think might be the main idea,  keep reading and see whether the details confirm it. If the details do not support that sentence as the main idea, then it isn’t.

Illustrative example

To illustrate what I said, I will give you 2 examples, one in which topic sentence is found the paragraph and the other with an implied main idea. Now, let’s start.

Example 1:

Sushi has become very popular in the US. Do you want to learn how to eat it in the traditional way? It’s simpler than you think. Specifically, there are 3 steps in the traditional way of eating sushi .First, forget the chopsticks, and use your fingers to pick it up. Next, dip the sushi, fish side down, in soy sauce, but use just a little for extra flavor. Finally, put the whole piece in your mouth.

So can you guess whether this paragraph contains topic sentence? The answer is “yes”. In a word, the topic may be “sushi” as “sushi” repeats many times in the paragraph. However, is it enough to be a topic? Actually, it’s too general. If you read the first sentence, you may think that the paragraph will talk about how sushi has become popular. However, in fact, when you read the remaining of the paragraph, it’s about how to eat sushi in the traditional way and therefore, it should be the topic. After finishing reading, you may conclude that there are 3 steps in the traditional way of eating sushi, so it’s topic sentence indicating main idea.

Example 2:

During a volcanic eruption, the wind can blow tons of volcanic ash long distances and cause nasal irritation, sore throats, and upper respiratory problems. Entire cities and crops can be destroyed under thick layers of ash. However, when it breaks down over time, volcanic ash becomes new, fertile soil. Farmlands on volcanic soil produce abundant crops.

So what’s the topic? Is it volcanic eruption? No, it’s more specific. In fact, it’s about volcanic ash and you can find it many times in the paragraph. Hence, volcanic ash is the topic.

What does writer say about the topic? In the first and second sentences (major supporting details), you can see that they mention how hazardous the volcanic ash is. But in the two last sentences (major supporting details), we can see that the volcanic ash may be beneficial. As a result, we can infer that volcanic ash can be both hazardous and beneficial. That’s the main idea.


In this post, I introduced you 4 components of a paragraph which are topic, main idea, major supporting details, and minor supporting details. The main idea can be expressed by a topic sentence in a paragraph or implied by major supporting details.

To find the main idea, you can simply apply my 2-step approach. First, you must identify the topic and finally determine what writer want you to know about the topic by reading details to recognize patterns.

Thank you for reading my blog.

See you in my next posts




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2 Responses

  1. Colin says:

    Tremendous awareness, appreciate your posting this
    I must say I have received a good deal of insight from this document, continue the good work, thank
    you so much.

  1. May 5, 2017

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