what is a controlling idea in an essay

Topic Sentence and Paragraph Organization

Paragraph organization refers to the way sentences are structured and ordered to create a unified and cohesive body of text.

The principal features to consider in paragraph organization are the topic sentence and controlling idea, supporting details, organizational patterns, and signal words. Together, these features develop a topic and connect ideas from one point to the next, logically and fluidly. This resource explains these features and provides numerous examples of paragraph organization.

The Topic Sentence and Controlling Idea

Similar to a thesis statement, which establishes the central focus or point of a whole piece of writing, a topic sentence works at the paragraph level to express the focus and general point of an individual paragraph. A topic sentence has two parts: 1) the topic that is being discussed throughout the paragraph and 2) a controlling idea that limits the focus on the topic to one point or idea. Each additional sentence in the paragraph then develops or expounds on that point with supporting details. The example topic sentence below is from a body paragraph in an informative essay.

Example Topic Sentence and Controlling Idea

The economy also plays a role in an increase in prescription pain reliever addiction.

The example topic sentence suggests the paragraph topic is “the economy,” and the controlling idea about the economy is how it “plays a role in an increase” in opioid addition. The signal word “also” connects this topic as an additional example or contributing factor to the opioid epidemic, the focus of the paper. The example below shows the topic sentence in the context of the complete paragraph.

The economy also plays a role in an increase in prescription pain reliever addiction. According to Jungeun Olivia Lee, a social work professor at University of Southern California, “The relationship between joblessness and substance abuse is strongest among people from low socioeconomic brackets, who might not be able to afford healthier ways to relieve their stress” (2017, as cited in Khazan, 2017, para. 8). Additionally, every point the unemployment rate rises, opioid-related death rates rise by almost 4 percent (Khazan, 2017). Unemployment makes it not only difficult for those suffering from pain to afford medication or healthy alternatives, but it can also contribute to depression and varying degrees of self-medication and addiction.

Supporting Details

In a paragraph, the topic and controlling idea are developed with supporting details. Listed here are some types of supporting details found in paragraphs along with an example of each in a sentence.

Facts: statistics or evidence from research that can be verified

The office sold seven million dollars of real estate during the boom years.

Opinions: statements, quotes, or paraphrases from subject matter experts

According to expert tea maker, Millie Stoff, there are three easy steps to making tea.

Definitions: explanations of what a term or concept means

A crossover is a family vehicle with the features of a sedan, a mini-van, and an SUV.

Examples: parts, pieces, instances, traits, or specimens that illustrate the essence or character of a greater whole.

Mario is a shy, introverted young man. For example, he has few friends and mostly keeps to himself.

Anecdotes: narrative accounts of one time or recurring events

When I visited the Washington Monument, I enjoyed the 180-degree view the most.

Descriptions: a visual or sensory depiction of a person, place, event, activity, or idea

Frostbit leaves crunched beneath our winter boots on the path through the snow-frosted trees.

Example Paragraph and Analysis of the Supporting Details

Hiking can be exhilarating during snowy winter months. When my friend and I visited North Carolina last January, we hiked in the Blue Ridge Mountains near the highest peak, Mount Mitchell, which is6,684 feet above sea level. We first crossed a foot bridge over a rapidly moving, ice-cold river and then followed a wooded trail up to a waterfall. Frostbit leaves crunched beneath our winter boots on the path through the snow-frosted trees. We saw deer and rabbits as we trekked up the path. I assure you that nothing feels better than inhaling crisp mountain air, but the neatest part of hiking in winter, besides the beauty of the mountain, is exhaling and seeing my breath turn to frost when it hits the cold air!

The topic sentence in the example paragraph indicates that the paragraph is on “hiking,” and the focus is that hiking is “exhilarating” during winter. The sentences in the paragraph support and develop this idea with an anecdote of the writer’s experience hiking up a mountain during winter. An anecdote is a narrative account that helps a reader understand an event or situation. Had the writer said hiking was “dangerous” instead of “exhilarating,” the anecdote in addition to the visual and sensory details, facts, and opinions about the experience would have been different. Additionally, while the sample paragraph is a personal account, writers in many professions use anecdotal evidence to report events from an objective point-of-view, where the writer is not a participant but rather a witness or observer.

Paragraph Organization

Along with having topic sentences and supporting details, paragraphs are also organized to achieve a certain purpose. However, just as a paragraph can contain different types of supporting details, a paragraph may also include more than one organizational pattern. Listed here are some common patterns for organizing a paragraph:

Cause and Effect for showing how one thing leads to another
Chronological Order for narrating events that occurred over time
Classification for grouping things together according to their features
Comparison and Contrast for showing how things are similar or different
Definition and Example for defining a term or idea and then expanding it with examples
Description for listing details
Episode for presenting details or information about a specific event or anecdote
General/Specific Order for presenting a general idea followed by specific examples
Generalization/Principle for making a general statement or applying a broad principle to explain the supporting details
Listing for presenting ideas from least to most important
Order of Importance for building up to or leading away from the most important point.
Problem and Solution for presenting an issue and a way to address it
Process/Cause for explaining what or how something happens and then why
Spatial Order for ordering details directionally

Signal Words

Signal words are signposts or clues to a paragraph’s organization. If the word “type” is used in a sentence, for example, it signals that the ideas involve types or classification, which is an organizational pattern. Signal words are context clues that hint at what the paragraph is about and how it is organized.

Listed here are signal words associated with different types of paragraph organization.

Cause and Effect : because, consequently, for this reason, hence, and on account of
Chronological Order : after, at last, at (time), as long as, at the same time, as soon as, before, during, eventually, finally, in (month or year), later, meanwhile, next, on (day or date), since, second, subsequently, then, until, and whenever
Classification : categories, classes, classifications, elements, features, groups, kinds, methods, types, varieties, and ways
Comparison and Contrast : another, both, however, likewise, one difference, on the other hand, on the contrary, similarity, similarly, unlike, and while
Definition and Example : concept, defined as, described as, e.g., for example, for instance, i.e., illustrates, is, is called, is stated, known as, means, refers to, specifically, such as, term, and that is to say
Description : above, across, along, appears to be, as in, behind, below, beside, between, down, in back of, in front of, looks like, near, onto, on top of, outside, over, such as, to the right/left, and under
Episode : a few days/weeks later, around the same time, as a result of, as it is often called, because of, began when, consequently, for this reason, just, lasted for, led to, shortly thereafter, since then, subsequently, this led to, and when
General/Specific Order : for example, for instance, indeed, in fact, in other words, like, namely, such as, and that is
Generalization/Principle : additionally, always, because of, clearly, conclusively, first, for instance, for example, furthermore, generally, however, if…then, in fact, it could be argued that, moreover, most convincing, never, not only…but also, often, second, therefore, third, truly, and typically
Listing : additionally, also, and, as well as, besides, furthermore, in addition, in fact, moreover, or, plus, and too
Order of Importance : central, chief, ending with, finishing with, key, lastly, least, main, major, finally, primary, principal, and significant
Problem and Solution : answer, challenge, difficulty, dilemma, enigma, indicate, improve, issue, need, plan, problem, propose, resolve, respond, solve, and suggest
Process/Cause : accordingly, as a result of, because, begins with, consequently, effects of, finally, first, for this reason, how to, how, if…then, in order to, is caused by, leads/led to, may be due to, next, so that, steps involved, therefore, thus, and when…then
Spatial Order : above, below, behind, beside, down, east, feels, highest, looks, lowest, next to, north, smells, sounds, south, tastes, under, and west

Sample Paragraphs and Analyses of the Organization

The sample paragraphs in this section illustrate topic sentences, supporting details, organizational patterns, and signal words in context. Read each paragraph to identify the type of paragraph organization on your own, and then proceed to the analysis to check your comprehension.

Sample Paragraph 1

In 1995, Lawrence started his real estate business, and it has since become a huge success. When Lawrence Real Estate opened its door in Oviedo, Florida, it sold seven million dollars of real estate during the first few boom years. By 2000, Lawrence decided to open two branch offices: one in Tampa in 2003 and one in Miami in 2004. By 2007, the home office and both the branch offices had survived the economic slowdown, so Lawrence and his associates expanded their business to the Carolinas and opened a branch office in Charlotte in 2020. It can be safely said that Lawrence Real Estate has become a model for success despite economic struggles and real estate devaluation.

Analysis of Paragraph 1: According to the topic sentence, which contains two coordinating clauses and therefore two subjects and two topics, this paragraph is about Lawrence and his real estate business, and the controlling idea is that they have been successful.

To understand how the supporting details are organized to present information about this topic and idea, the reader can consider the supporting details. To do this, they look at the way the sentences begin and at any signal phrases that lead readers along a certain line of thinking. Here are some key signal words: “in 1995,” “By 2000,” “By 2007,” and “in 2020.” These dates make a pattern. They go back to 1995 and then in a chronological order, they move forward to when the success of the business happened.

This paragraph uses chronological order . The reader will notice too that the last sentence returns to the beginning idea of 15 years ago. In this sentence, a final comment about the time period overall is given with respect to the new information

Sample Paragraph 2

Making a great cup of tea is easy if you follow these three steps. First, heat a cup of water to the boiling point. Then put the tea bag in the hot water, and let it steep for at least three minutes. Finally, add creamer and sugar to taste. There is nothing tastier than a strong cup of tea early in the morning.

According to the topic sentence, which is the first sentence of the paragraph, making a cup of tea is the topic, and the controlling idea is that it’s easy to do if you follow three steps. Signal words open the following sentences: “first,” “then,” and “finally.” These indicate a sequence of steps, not times or dates as in a narrative story, but steps that happen in a specific order as in the process of doing something or informing others how to do something.

This paragraph uses process order (or process/cause). In the last sentence of this paragraph, the process is completed with a return to the original topic—a cup of tea—and a new comment about it—that a strong cup is tasty in the morning, making those three steps not only easy but also worthwhile.

Sample Paragraph 3

The Washington Monument is divided into three main areas. The lowest section of the building houses the entrance, a gift shop, and a restaurant. The middle section consists of elevators and stairways to the top. The top section of the monument includes an observation deck with a spectacular view of the Washington D.C. area. When I visited the Washington Monument, I toured every section but enjoyed the spectacular 180-degree view the most.

Based on the topic sentence at the beginning of the paragraph, the topic is the Washington Monument, and the controlling idea is that it is divided into three main areas. The paragraph presents information about the lowest section first, the middle section second, and the top section third. The last sentence makes a remark about the most enjoyable of all the sections. This is an example of spatial organization . The information is given in the order you might see it if you were there.

Sample Paragraph 4

There are three types of family vehicles made in the United States. The first type is the minivan. All American car manufacturers make a version of the minivan. Some say that the comfort and amenities of the minivan compare to none. The second type of family vehicle is the SUV. Some SUVs offer four-wheel-drive to navigate tough terrains, and they also offer seating for a large crowd. A third type of family vehicles is called the crossover. These vehicles supposedly have the best features of the sedan, minivan, and SUV. They are easy to maneuver, look much like a regular sedan, and sit up to six people. All of these vehicles are family friendly; they offer safety, roomy comfort, and many extra features to accommodate the special needs of families.

This paragraph shows another way to organize the details of a topic. The topic sentence of this paragraph is structured differently than the previous ones. Typically, the topic of a sentence is also the grammatical subject, but the subject in this sentence is “there,” a pronoun, and the topic that tells what the paragraph is about, “family vehicles,” is in the predicate of the sentence. The controlling idea is that there are three types made in the U.S.

The paragraph is organized according to those three types: the first type, the second type, and the third type. To conclude, there is a comment about “all of these vehicles” or all of these types of vehicles. When information is organized by types or features, the information is classified. This type of organization is classification .

Sample Paragraph 5

Although the twin brothers share many physical characteristics, they handle themselves differently in social situations. Mario is a shy introverted young man. He has few friends and mostly keeps to himself. On the other hand, Gino is outgoing and the life of the party. Unlike Mario, Gino has many friends and feels totally at ease among big crowds. The best way to tell these identical twins apart is to invite both to a party and observe how differently they interact with the other guests.

When the topic sentence is complex (having more than one clause) as in this paragraph, there may be two subjects and therefore two topics; however, here, the subject of the first clause is “the twin brothers” and the subject for the second clause is “they,” so both subjects refer to the same topic—the twin brothers. The controlling idea is that the twin brothers share many physical characteristics but handle themselves differently socially.

The paragraph then progresses with descriptions of these similarities and differences. Contrast is created by signal phrases and words such as “although, “on the other hand,” and “unlike.” Words such as “apart” and “differently” also indicate that the organizational pattern of this paragraph is comparison and contrast .

Sample Paragraph 6

There are many reasons why I enjoy walking tours when visiting new cities. For starters, walking through a city allows the visitor to see the details of an area without having to hurry. This often results in meeting locals and experiencing their lives and traditions first hand. Furthermore, walking tours are flexible and inexpensive because there are no strict schedules or transportation expenses. Travelers taking walking tours are rewarded with firsthand experiences in the places they visit and the opportunity to personally interact with the people who live there.

Because the first sentence begins with “there are,” the reader must move beyond the subject and verb to find the topic. Additionally, this is a complex sentence with an independent and dependent clause connected by “why,” so there may be two topics. Looking at the objects of both clauses, the reader finds “many reasons” and “walking tours.” These two topics are linked together by the controlling idea: the writer enjoys walking tours while visiting new cities for many different reasons.

The signal words build on this idea of “why” with terms such as “results” and “because.” The last sentence then sums up the ultimate effect of walking tours: Travelers are rewarded. This is an example of cause and effect organization.

Sample Paragraph 7

Hiking can be especially exhilarating during snowy winter months. When my friend and I visited North Carolina last January, we hiked in the Blue Ridge Mountains near the highest peak, Mount Mitchell, which is 6,684 feet above sea level. We first crossed a footbridge over a rapidly moving, ice-cold river and then followed a wooded trail up to a waterfall. Frostbit leaves crunched beneath our winter boots on the path through the snow-frosted trees. We saw deer and rabbits as we trekked up the path. I assure you that nothing feels better than inhaling crisp mountain air, but the neatest part of hiking in winter, besides the beauty of the mountain, is exhaling and seeing my breath turn to frost when it hits the cold air!

In the first sentence, the topic of the paragraph is “hiking,” and the comment or main idea is that it “can be especially exhilarating during snowy winter months.” Based on this, the reader can expect supporting details to illustrate this exhilaration, but they do not know how it is organized until they look at the signal words that help progress the topic from one idea to the next.

Taking inventory of the signal words, the reader will find several time markers: “When” and “last January” set the narrative in the past while “first” and “then” develop a chronological order of events. The final summarizing sentence about hiking “in winter” reminds the reader of the season.

Within this chronology , signal words are associated with spatial organization: “over,” “up,” “beneath,” “through,” “crunched” (sounded), “saw,” “feels,” and “seeing.” Narratives typically include descriptive elements about the setting. Additionally, the concluding thought contrasts “inhaling” to “exhaling.” The reader can thus conclude that this paragraph has multiple patterns of organization that are intricately connected.