We are now going to practice finding the main idea in a paragraph. To understand the difference between a main idea and the topic, imagine that your friends are talking about their pets, but you are not paying much attention to them. If someone asks you what the topic of their conversation is, you might say “pets.” But because you are not listening to the whole conversation, you might not know that the “main idea” is whose pet is the most obedient. Topics are very broad, and main ideas are more specific. We are going to be working on using a main idea to write topic sentences. The sentences in the paragraph below contain examples that illustrate the paragraph’s main idea. The paragraph is from the reading for this week, A Scandal in Bohemia:
To Sherlock Holmes she is always the woman. I have seldom heard him mention her under any other name. In his eyes she eclipses and predominates the whole of her sex. It was not that he felt any emotion akin to love for Irene Adler. All emotions, and that one particularly, were abhorrent to his cold, precise but admirably balanced mind. He was, I take it, the most perfect reasoning and observing machine that the world has seen, but as a lover he would have placed himself in a false position. He never spoke of the softer passions, save with a gibe and a sneer. They were admirable things for the observer—excellent for drawing the veil from men’s motives and actions. But for the trained reasoner to admit such intrusions into his own delicate and finely adjusted temperament was to introduce a distracting factor which might throw a doubt upon all his mental results.
The main idea of this paragraph is in the first sentence. The first sentence identifies the two characters described in the rest of the paragraph and suggests what their relationship to one another is. Each sentence that follows either describes the woman, Sherlock Holmes, or how he felt about the woman.
Here is another example from the same story. See if you can find the main idea:
One night—it was on the twentieth of March, 1888—I was returning from a journey to a patient (for I had now returned to civil practice), when my way led me through Baker Street. As I passed the well-remembered door, which must always be associated in my mind with my wooing, and with the dark incidents of the Study in Scarlet, I was seized with a keen desire to see Holmes again, and to know how he was employing his extraordinary powers. His rooms were brilliantly lit, and, even as I looked up, I saw his tall, spare figure pass twice in a dark silhouette against the blind. He was pacing the room swiftly, eagerly, with his head sunk upon his chest and his hands clasped behind him. To me, who knew his every mood and habit, his attitude and manner told their own story. He was at work again.
Which of the sentences below contains the main idea of the paragraph?
A. “One night—it was on the twentieth of March, 1888—I was returning from a journey to a patient (for I had now returned to civil practice), when my way led me through Baker Street.”
B. “As I passed the well-remembered door, which must always be associated in my mind with my wooing, and with the dark incidents of the Study in Scarlet, I was seized with a keen desire to see Holmes again, and to know how he was employing his extraordinary powers.”
C. “His rooms were brilliantly lit, and, even as I looked up, I saw his tall, spare figure pass twice in a dark silhouette against the blind.”
D. “He was pacing the room swiftly, eagerly, with his head sunk upon his chest and his hands clasped behind him.”
The correct answer is “A.”
The first sentence tells you who is speaking, what is happening, and that this person is going into a particular place. Each of the other sentences describes the place where he is going, what it looks like, and who was in there. “B” is not as strong a choice as “A” because it refers to A Study in Scarlet and Holmes’s powers, which are not described in the rest of the paragraph. Choice “B” is too specific to be the main idea of this paragraph. Choices “C” and “D” are not correct because they are describing Holmes’s actions, which are not what the whole paragraph is about.
Let’s try one more. Read the following and select the sentence from the list below that contains the main idea.
At three o’clock precisely I was at Baker Street, but Holmes had not yet returned. The landlady informed me that he had left the house shortly after eight o’clock in the morning. I sat down beside the fire, however, with the intention of awaiting him, however long he might be. I was already deeply interested in his inquiry, for, though it was surrounded by none of the grim and strange features which were associated with the two crimes which I have already recorded, still, the nature of the case and the exalted station of his client gave it a character of its own. Indeed, apart from the nature of the investigation which my friend had on hand, there was something in his masterly grasp of a situation, and his keen, incisive reasoning, which made it a pleasure to me to study his system of work, and to follow the quick, subtle methods by which he disentangled the most inextricable mysteries. So accustomed was I to his invariable success that the very possibility of his failing had ceased to enter into my head.
A. “At three o’clock precisely I was at Baker Street, but Holmes had not yet returned.” “The landlady informed me that he had left the house shortly after eight o’clock in the morning.”
B. “The landlady informed me that he had left the house shortly after eight o’clock in the morning.”
C. “I sat down beside the fire, however, with the intention of awaiting him, however long he might be.”
D. “I was already deeply interested in his inquiry, for, though it was surrounded by none of the grim and strange features which were associated with the two crimes which I have already recorded, still, the nature of the case and the exalted station of his client gave it a character of its own.”
The answer this time is “D.”
The way to find the answer is to ask what each answer refers to. “A” refers to the location, “B” refers to Sherlock Holmes’s absence, “C” to Dr. Watson waiting, and “D” to Holmes’s investigation. The next step is to ask which of these is the paragraph’s main idea. The paragraph is mainly about the investigation, which means that “D” is the correct answer. This example may have thrown you off because the main idea came in the middle of the paragraph instead of at the beginning. Be careful to read through the entire paragraph each time, and to look at each sentence and its role within the paragraph. The main idea often appears right at the beginning of a paragraph—but not always!
Attribution: This page adapted from “Washington State Board for Community and Technical Colleges: Finding the Main Idea (Unit 1.2.1)” in the ENGL000: Pre-College English course, by Washington State Board for Community and Technical Colleges, Saylor Academy (2019). License: CC BY.
