Your introduction paragraph should grab your reader's attention, introduce the topic of your essay, and present your thesis. (The thesis is the main idea of the essay.) As you introduce your topic, make sure to give the reader enough background information about the topic that the reader will be able to understand the thesis.
You can visualize the ideas in your introduction paragraph by thinking about an inverted triangle. The ideas in the beginning of your introduction paragraph are general. Then you narrow down the topic to a specific idea.
Grab the reader's attention and introduce the topic.
The very first sentence of your introduction should get your reader interested in your topic. The first sentence of an introduction is called a "hook." There are many types of hooks: facts, questions, problems, descriptions, etc.
Present your thesis.
The thesis states the main idea, or focus, of the essay. The rest of the essay will give evidence and explanations that show why or how your thesis is true.
An effective thesis—
—addresses the prompt if there is one* (i.e., answers the question).
—is usually at the end of the introduction paragraph.
—controls the content of all of the body paragraphs.
—is a complete sentence.
—does not announce the topic (e.g., "I'm going to talk about exercise.").
—should not simply be a fact (e.g., "Many people exercise.").
—should not be too general (e.g., "Exercise is good.").
—should not be too specific (e.g., "Exercise decreases the chance of developing diabetes,
heart disease, asthma, osteoporosis, depression, and anxiety.").
—may state main points (e.g., "Exercise is essential because it improves overall physical and
—may imply main points (e.g., "Exercise is essential for improving our well-being.").
*In some essays you write, you will not have a specific question to answer. Instead, you may need to choose your own topic. Your essay should still answer a question (e.g., how are typical Japanese and Chinese diets similar or different?).