in this article where in an essay do you include topic sentences? Explain the purpose of a topic sentence

Narrative and Descriptive Writing
You most likely read paragraphs every day and don’t give them much thought. A paragraph is a collection of related sentences dealing with a single topic. Learning to write a good paragraph is a valuable skill. Well-written paragraphs will help you stay on track during your drafting and revision stages. They also allow your reader to follow your thoughts in a clear, organized manner.

When writing a paragraph, there is basically only one rule that you must follow: stick with one subject per paragraph. Your paragraph should contain one main idea and then give some supporting details. If you are writing a lot about one of the supporting details, this may be moved to a new paragraph.

Elements of a Paragraph
A paragraph should contain the following elements: unity, coherence, a topic sentence, and adequate development. Many of these elements overlap. Let’s take a closer look at each element.

Unity means that the paragraph has a single focus. It sticks to one main idea. Coherence is what makes a paragraph easily understandable. You create coherence in your paragraphs with logical bridges and verbal bridges.

Logical bridges are used when the same idea of a topic is carried over from sentence to sentence. Verbal bridges are when key words are repeated in several sentences or when transition words are used to link ideas from different sentences.

A topic sentence indicates in a general way what idea or thesis the paragraph is going to deal with. A topic sentence can occur anywhere in the paragraph—beginning, middle, or end. However, it most frequently comes at the start of the paragraph to alert the reader as to what the paragraph will be about.

The topic that is introduced by a topic sentence should be discussed adequately. The length of a paragraph may vary, but paragraphs that are only 2–3 sentences may not be fully developed.

Narrative and Descriptive Paragraphs
One type of paragraph is a narrative paragraph. This type of paragraph tells a story. You will find this type of paragraph mainly in fiction. Narrative writing is usually chronological with a sequential presentation. It usually includes a setting, characters, problem, and solution.

Descriptive paragraphs are those that describe. They offer vivid details that allow readers to visualize or understand the topic. A lot of sensory language is used in this type of writing. This type of writing can be tricky to compose because it may come across as flat. In this descriptive paragraph, the details are underscored and the topic sentence is highlighted:

Calloway Gardens in south Georgia is an outstanding resort. The resort is surrounded by majestic trees, some of which are more than a century old. During the summer months, time can be spent floating lazily in the cool lake water. Fall brings a change of foliage and cool, crisp air. In the winter, one can drive through a symphony of sparkling lights. During the spring, visitors enjoy the vibrant blossoms of the six acres of carefully manicured gardens and wander through the butterfly gardens. Calloway Gardens is a magical place that has something for everyone throughout the year.

Checklist
Now you have learned how to write a well-developed paragraph. It can be useful to use a checklist of items to help determine whether you have written a well-developed paragraph.

Does my paragraph have:

_____ unity (one main idea)

_____ coherence (logical or verbal bridges)

_____ a topic sentence (summarizing the paragraph’s main idea)

_____ adequate development (at least three sentences; topic sentence idea fully discussed)

In the essay, topic sentences should be included in each paragraph. The purpose of a topic sentence is to introduce the main idea or thesis of the paragraph and provide a preview of what will be discussed. It helps to create cohesion and organization within the essay, and allows the reader to easily follow the writer's thoughts.