Identifying Main Ideas

Explicit Main Idea

A main idea is the author’s controlling point about the topic.  It usually includes the topic and the author’s attitude or opinion about the topic.  To identify the main idea, ask yourself:

  1. Who or what is the paragraph about?  The answer is the topic.  The topic can be stated in just a few words.
  2. What does the author think about the topic?  The answer is the point. The point can also be stated in just a few words.

Once you’ve identified these pieces, you can combine them to state the author’s main idea in a single sentence.

Topic= the cool-down period

Point = important parts of exercise workouts

The cool-down period is an important part of an exercise workout.

Topic + Point = Main Idea

Often, but not always, the main idea of a paragraph is written as that paragraph’s topic sentence.  A topic sentence is a single sentence that states the topic and words that qualify the topic by revealing the author’s opinion about the topic or the author’s approach to the topic and also reveal the author’s thought pattern or organizational strategy. When you’ve identified both the main idea and the thought pattern, you can identify the topic sentence.

Main Idea = The cool-down period is an important part of an exercise workout

Thought Pattern = several reasons

The cool-down period is an important part of an exercise workout for several reasons.

Main Idea Thought Pattern = Topic Sentence

Placement of Main Ideas & Topic Sentences

General to Specific

The topic sentence is the one sentence that is general enough to include all the ideas in the paragraph.  Therefore, a topic sentence that begins a paragraph or appears within the first few sentences of a paragraph signals a move from general ideas to specific ideas.  

Specific to General to Specific

At times, an author begins a paragraph with details to stir the reader’s interest in the topic.  The flow of ideas moves from the specific to the general and back to the specific.

Specific to General

Sometimes, an author waits until the end of the paragraph to state the topic sentence and main idea.  This allows the details to build up to the main idea and is sometimes called “climactic order.”

Implicit Main Idea

Implied Main Idea

This is a main idea that is not stated directly but is strongly suggested by the supporting details in the passage.  Many paragraphs in college textbooks do not provide a topic sentence, instead using supporting details to imply the main idea.  To determine the implied main idea, look at:

  1. The topic
  2. The supporting details: facts, examples, descriptions, and explanations given
  3. The author’s thought pattern
  4. The author’s purpose

Read the sample paragraph below:

Egypt’s pyramids are the oldest existing buildings in the world.  These ancient tombs are also among the world’s largest structures.  The largest pyramid stands taller than a 40-story building and covers an area greater than that of ten football fields.  More than 80 pyramids still exist, and their once-smooth limestone surfaces hide secret passageways and rooms.  The pyramids of ancient Egypt served a vital purpose: to protect the pharaoh’s bodies after death.  Each pyramid held not only the pharaoh’s preserved body, but also all the goods he would need in his life after death.  

1.The topic of the paragraph is pyramids

2.There are three groups of supporting details, discussing: age, size, and purpose

3.The author has organized the supporting details into “characteristics” or “traits” of the pyramids.

4.The author purpose seems to be trying to define a pyramid.

Implied Main Idea: Pyramids are structures with several distinctive traits.

Remember, the main idea must be broad enough to cover all the details in the paragraph without being so broad that it includes details not mentioned.  



By Vanessa Flora-Nakoski | This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. To view a copy of this license, visit

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