Module: Reading Techniques

FINDING THE MAIN IDEA IN PARAGRAPHS

By dividing long passages of text into smaller blocks, writers make their written material more
readable. These blocks of text are called paragraphs. Each paragraph in a piece of writing about a subject
is a group of sentences dealing with one idea related to that subject. The main idea in a paragraph
expresses the particular point the author is trying to make about a subject.

One useful way to understand the main idea of a paragraph is to start by identifying the paragraph’s
topic. A paragraph’s topic is the subject under discussion. When identifying the topic of a paragraph,
remember that it should be general enough to cover the material in the paragraph, but not so general that
the label could apply to many paragraphs.

When the main idea is stated in a sentence, we call it the topic sentence of the paragraph. Although it
is often found at the beginning or at the end of the paragraph, the topic sentence can be found anywhere in
the paragraph. The topic sentence is typically the most general sentence in the paragraph, and the
remaining sentences provide specific evidence and discussion to "back up" the main idea expressed in the
topic sentence. The evidence or support for the main idea can be in the form of reasons, details, facts,
and/or examples. Transition words often signal this support.

In the following paragraph about alcohol, the main idea is found in the topic sentence, the first
sentence of this paragraph, which makes the point that alcohol affects the brain and nervous system in
many ways. The rest of the paragraph gives information about how the brain and nervous system are
affected. We have also highlighted some transition words that signal each supporting point and show a
relationship between them.

Alcohol affects the brain and nervous system in many ways. Initially, only the cortex of the brain is
involved--the user experiences loss of judgment, willpower, and self-control. Then, when the cerebrum
becomes involved, the vision is blurred and the speech is slurred. As the cerebellum becomes involved,
the ability to coordinate the muscles is lost. Dizziness, staggering, and eventually the inability to walk
indicate that total muscle coordination is lost. Finally, total helplessness, unconsciousness, and possibly
death may result as alcohol overcomes the entire nervous system.

Sometimes the main idea of a paragraph is not directly stated in one sentence, but is implied or
suggested by all of the sentences in the paragraph. In this case, the reader is expected to provide the main
idea for the paragraph by considering the information given and drawing a conclusion as to what the
general idea behind the information might be. Read the following paragraph.

Between 1846 and 1854 the potato famine caused starvation, forcing one and a half million Irish to leave
their country. Others left because they were denied religious freedom. They were not allowed to worship
as they pleased. Still others left to rejoin the members of their families who had moved on.
There is no sentence in this paragraph which directly states, "There were several reasons why the Irish left
their homeland." That idea is only suggested by the facts presented. The sentence above would be an
effective topic sentence for that paragraph, however, because it is a general statement which incorporates
the information presented by all of the sentences in the paragraph.

Topic vs. Main Idea

“First, it is very important to recognize the difference between the topic of a reading selection and the
main idea”.
So what is the difference between the topic and the main idea?
EX: If you are not sure of the difference, it might be helpful to use your prior knowledge and think of
what you do know of topic and main idea. Since most of us like movies, it could be helpful to think of
topic and main idea in terms of a film. Some of us have seen “12 years a slave”.
- The topic of the movie is: “SLAVERY and the struggle for freedom”
- The main idea is: Based on an incredible true story of one man's fight for survival and
freedom. In the pre-Civil War United States, Solomon Northup, a free black man from upstate
New York, is abducted and sold into slavery. Facing cruelty (personified by a slave owner), as
well as unexpected kindnesses, Solomon struggles not only to stay alive, but to retain his
dignity. In the twelfth year of his unforgettable odyssey, Solomon's chance meeting with a
Canadian abolitionist will forever alter his life.
-The topic of a selection is the subject matter, what it is about. It usually is expressed in a word or
phrase.
-The main idea is what the author says concerning the topic.
Practice:
“See example 01”
“Smoking has been proven dangerous to people’s health, yet many continue to smoke for various
reasons. For young people, smoking often represents maturity and individuality. Many smoke as a
way to reduce tension. In addition, the regular smoker becomes addicted psychologically and
physically to the nicotine in cigarettes”.
Topic: a. Health c. Addiction b. Smoking d. Nicotine

Main Idea:
a. Smoking has been proven dangerous to people’s health in various ways.
b. Regular smokers become addicted to nicotine.
c. Although smoking is dangerous, people continue doing it for various reasons.
d. Nicotine is what smokers become addicted to, both psychologically and physically.
 Main Idea vs. Supporting Detail

After you identify the topic of a selection, you then are on your way to finding the main idea. As you read
through a reading selection, you must distinguish between the main idea statements and the supporting
details.

What is the difference?

“Details explain, illustrate, and elaborate upon the main idea. Details are specific pieces of information.
Main idea statements are general and broader”.

“See Example 02”

“There is some evidence that colors affect you physiologically. For example, when subjects are
exposed to red light respiratory movements increase; exposure to blue decreases respiratory
movements. Similarly, eye blinks increase in frequency when eyes are exposed to red light and
decrease when exposed to blue. This seems consistent with intuitive feelings about blue being more
soothing and red being more arousing. After changing a school’s walls from orange and white to
blue, the blood pressure of the students decreased while their academic performance improved”.
What is the topic? What is the main idea? What are the details?
Now that you understand the distinction between the topic and the main idea and supporting details,
you might wonder how you locate the main idea of a reading selection.

Tip: “The main idea of a paragraph or essay or textbook chapter is stated explicitly about half of
the time. It makes sense that you first look to see if there is a main idea sentence”.
topic sentence in a paragraph.
thesis or thesis statement in an essay or article.
red to as the theme.
Location of the topic sentence
- One common place for the topic sentence of a paragraph is in the beginning. See Ex 02
- However, topic sentences are not always the first sentence in a paragraph. Sometimes, a topic
sentence may be in the middle. Here is an example of main idea in the middle. See EX 03

“See Example 03”

“Unlike people in the United States, who believe that different individuals have different
abilities, the Japanese believe that all students have much the same innate ability and that
differences in academic performance must be due to differences in effort. Therefore, the key to
superior performance is hard work, which begins at an early age. Before most Japanese
children even enroll in school, their parents—usually their mothers—have taught them
numbers, the alphabet, and some art skills. By age four, more than 90% of Japanese children
are attending preschool in order to receive a head start on their education. The typical Japanese
student spends six to seven hours a day in school, five full days a week and a half-day on
Sunday”

- Sometimes a topic sentence may be at the end of a paragraph as represented in this type of
structure. See Ex 04
 “See example 04”
People do it every day. They log on to their favorite website and browse for hours, checking
out bargains. They dump every possible wish into their shopping carts, knowing they can cast
each one aside before they finalize their purchases. On the way, they may enter a sweepstakes in
the hopes of winning a trip to Cuba, or maybe even a new SUV. And then, when they have
decided on their purchases, they enter private information without giving it a thought. With a
keystroke, they release their personal data into what may or may not be a secure zone. Despite
what much of the public believes, internet shopping is not safe.
- Sometimes, a writer may start a paragraph with a topic sentence and restate the main idea at the
end as well. See Ex 05

“See example 05”

The study of prehistoric humans is, of necessity, the study of fossil remains. To
begin to understand who our ancestors were and what they were like, we must be able to
interpret the fragments of them that are coming to the surface in increasing numbers.
Given fairly reliable methods to determine their age, we can now turn with more
confidence to primate fossils for an answer to the all-important question: How do we tell
monkeys, apes, and humans apart? For present-day species this is no problem; all have
evolved sufficiently so that they no longer resemble one another. But since they all have a
common ancestor, the farther back we go in time, the more similar their fossils begin to
look. There finally comes a point when they are indistinguishable. The construction of
a primate fossil family tree is essential if we are ever going to discover the line of descent
from early hominid to modern human.
-Summary
- Conclusion: “As an active reader, you must search for the sentence that states the central point, the
gist of the paragraph”.

Implied Main Idea

It is important to recognize that you may not always find a topic sentence in each paragraph. Sometimes
the main idea is implied. What this means is that there is not an explicitly stated main idea sentence but
one that you, as a reader, must figure out. The term most often used to describe this is inference. You
infer the main idea in this situation.

How Do You Understand An Implied Main Idea?

- First, identify the topic of the paragraph. What is this paragraph about?
- Then read carefully all the supporting details. What does the writer want you to know about the
topic?
- How do the details connect? What larger idea do they explain?
 - Express this idea in your own words. The implied main idea sentence must be broad enough to
cover all the details in the paragraph but must not be too narrow so that some details are left out.
Once you think you have formed the implied main idea in your own words, confirm your answer by
using some of the following strategies: • Does every major detail support it? • Does your answer
provide a general idea or summary for the details? • Try to mark the major supporting details and
notice what they have in common. • If one of your major details talks about something else, you’ll
have to rethink the implied main idea so that it is supported by all of them.
Let us look at an example.
“Birds that roost in communities keep warmer and save more energy than those who roost
separately. Another advantage to staying in flocks is that many birds are more likely to find food
and detect danger than a solitary bird—several pairs of eyes are better than one. In addition, birds
that eat on the ground with their flock can more easily escape attack because at least one member
of the flock will alert the others. Then, when all the birds fly upward to escape together, they cause
confusion, turning a predator’s interest away from any one individual. Several small birds may
even act together to “mob” a larger intruder and drive it away”.
Let’s go through these questions to figure out the implied idea:

1- What is the topic?

2- What does the writer want me to know about birds?
3- How do the details connect? What larger idea do they explain?

Main Idea in Longer Reading Selection

When you read longer articles and essays, you must also try to locate the main idea statement (a thesis or
thesis statement). About half of the time there will be explicitly stated thesis that you can find. Other
times, you will need to infer it.
How to Find the Main Idea in Longer Selections: Follow the same tips mentioned for finding the main
idea in paragraphs though with some modification.

 Look carefully not at just the first sentence but the first paragraph or two. Quite often, the thesis will be
in the introductory paragraph.
 Many times, the thesis will be presented in the introduction but also restated in the concluding
paragraph.

 Sometimes the main idea will be in the middle, often after a paragraph or two which may be used to
engage the reader or to provide background information.

 Last, there will be times when the main idea is implied. You then need to identify the topic, examine
all the supporting details, and then try to express the larger idea that unites the details as an implied main
idea statement.