4.3 Topic Sentences

Function and Elements of a Topic Sentence

A  topic sentence is usually the first sentence of a body paragraph. The purpose of a topic sentence is to identify the topic of your paragraph and indicate the function of that paragraph in some way.

In order to create an effective topic sentence, you should do the following:

1. Use a transitional device to effortlessly segue from the idea discussed in the previous paragraph.

When choosing a transitional device, you should consider whether your new paragraph will build onto the topic of your previous paragraph, begin to develop a new key idea or sub-claim, or present a counterargument or concession.

See section 4.6 for information regarding when to begin a new paragraph and section 4.7 for help with transitional words and phrases.

2. Clearly identify the key idea or sub-claim that you intend to expand upon in your new paragraph.

Even if you are building onto the idea of the previous paragraph, you will still need to identify the sub-claim in your topic sentence. When constructing a topic sentence, you may feel as though you are stating the obvious or being repetitive, but your readers will need this information to guide them to a thorough understanding of your ideas.

3. Make a connection to the claim you make in your thesis statement.

It might help to think of your topic sentence as a mini thesis statement. In your body paragraph, you should be expanding upon the claim you make in your thesis. For this reason, you should link your topic sentence to your thesis statement. Doing so tells your readers, “This is the point I mentioned in my thesis that I now intend to support and either prove or explain further.”

To connect to your thesis, you should consider the function of the body paragraph, which will usually depend upon the type of essay you are writing; for example, your topic sentence should suggest whether your goal is to inform or persuade your readers (your topic sentence should indicate whether or not you have an opinion or perspective on the topic).