Introduction Paragraphs

Your introduction paragraph should grab your reader's attention, introduce the topic of your essay, and present your thesis.

Grab the reader's attention 

The very first sentence of your introduction should get your reader interested in your topic. Don't start out too generally in your introduction paragraph. Also, don't state all of your specific main points individually in the introduction.

Introduce the topic through background information

Focus on giving background information that your reader needs to understand the topic generally. The middle sentences of your introduction paragraph prepare your reader to understand your thesis statement. 

To know what background information you should include, you need to consider your audience. Are you writing an essay about electromagnetism for a scientific journal that will be read by other scientists in your field?   Are you writing a piece for a local newspaper about the effects of a recent local government policy change for the general public who don't know anything about the policy that was changed? Are you writing an essay analyzing poetry for your college English teacher?

You need to know who your audience is before you can start guessing what background information they already know and what background information you need to tell them for them to understand your thesis statement later. Fellow scientists might not need basic scientific words defined. However, they may need specific science concepts that few people are experts in explained and recent research about the topic reviewed to bring them up to date before they read your thesis statement. The average people of a town would probably need the new government policy defined and explained. If you tried to explain the effects of the policy when they don't even know what the policy is, they would be confused. Background information introduces the topic of the essay and prepares the reader to understand your main idea about that topic (your thesis statement).

When you are writing for a teacher in a class, assume that you are writing for a general audience unless your professor tells you otherwise. Assume your audience knows general knowledge like "Fire is hot.", but doesn't know specific things like "The pronunciation of English words changed during The Great Vowel Shift of the late middle ages."  If you are not sure if a piece of information is general knowledge or specific knowledge, ask a friend who doesn't know about your topic to read your introduction. They can point out what information they don't understand as a general reader. Then, you can add background information about those points.

*Pro Tip: Never use the phrase "Everyone knows..." in the background knowledge section because you need to assume the general audience doesn't know most of the things about your topic. 

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 or imply main points (e.g., "Exercise is essential because it improves overall physical and mental health." vs. "Exercise is essential for improving our well-being.").

A thesis statement should be concise. It should say the whole main idea in as few words as possible. This makes for a more pleasant experience for the reader who might get tired or confused reading long, unnecessarily complex sentences. Some main ideas are very complex and may take multiple sentences to say clearly, but most can be said in just one sentence. Writing your main idea concisely is preferred in academic writing. This is why single-sentence thesis statements tend to be more powerful than thesis statements that are multiple sentences long. 

However, the thesis statement sentence still needs to be grammatically correct. One of the more common errors with student essay writing is comma splice sentences in the thesis statement. A comma splice sentence is a sentence that doesn't properly use conjunctions; it just tries to connect all the clauses with commas only which is grammatically incorrect. There are also other common grammar errors such as run-on sentences, incorrectly placed periods, and a lack of commas to watch out for. Thesis statements are often only a single sentence long, but due to the complex grammar and need for specific wording, they can take more time to write than other sentences. Thesis statements may also be revised multiple times to get the grammar and the wording just right to express your idea most clearly.


Exercise 2.1: Background Information

Part A: Consider the prompt and the proposed thesis statement. Then answer this question: What background information would you need as a reader to understand the topic of this essay? 

Prompt: Describe either the causes or effects of a topic. The topic may be a problem (e.g., poverty) or a good thing (e.g., economic stability).

Thesis Statement: Therefore, the causes of high inflation rates, high unemployment rates, and the excess of money circulating in the market lead the Fed to enact monetary policies that are designed to help the US economy.

**Don't read part B until you are done with part A. **

Part B: Read the introduction below. Then answer the reflection questions below.

    One of the most and respectful Central Banks in the world is the Fed, Federal Reserve Bank, located in the USA. This bank is recognized by having the most effective policies that have been turning the USA economy one the most powerful economies in the world. Although the US economy had one of the most financial notable crises in the history during the Great Depression (during 1929 thru 1939), the US economy has been solid and stable for many years. Due to its stability in the economy, many foreign investors allocate their capitals to the US country in order to obtain their incomes. All these become possible because of the efficient actions done by the Fed. The Fed has the responsibility to control inflation, and other indicators that contribute to its economy. Therefore, the causes of high inflation rates, high unemployment rates, and the excess of money circulating in the market lead the Fed to enact monetary policies that are designed to help the US economy.

Reflection Questions:

  • Does the author answer the questions that you had?
  • Do you feel confident that you would understand the essay’s thesis statement based on the background information in the introduction? Why or why not?

Exercise 2.2: Thesis Analysis

Using the points above, decide whether or not each of the following thesis statements is effective:

  1. The murder of the last Inca emperor, an important event in the history that has had different impact in the Inca Empire. 
  2. Overuse of smartphones causes detrimental effects on the brain, unsatisfied relationships with others, and several physical problems.
  3. It was a place desert and uninhabited, but that place turned out to be one of the most important, beautiful, and futuristic cities around the world because they manage a stable economy, they started to gain recognition with the Burj Al Arab, that construction was interesting, fast, but struggling as well. 
  4. This essay will explain the effects of alcohol consumption on your body such as the effect on organs and the ability to control your actions. 

Exercise 2.3: Complex Main Idea Thesis Practice

Below is a chart of common subordinating conjunctions or conjunctive phrases. Use this chart to help write a complex or complex compound thesis statement that answers the prompt. You will need to answer both questions from the prompt in only one sentence. 

Subordinating Conjunctions:

after, although, as if, in order for
because, before unless, until
even though, even if where, whereas, while


Should a new railroad be built in your home state or province? What would the short-term and long-term effects of this decision be?


Exercise 2.4: Thesis Grammar Practice

Revise these thesis statements to be more concise and grammatically correct. Write your best version of the thesis statements on the line. 

1. The Chernobyl accident caused irreparable environmental and social damages. This gave the people an opportunity to become stronger through their unity and their courage to serve no matter the consequences. 


2. Due to the fact that students need to be focused 100% at school in order to achieve their dreams. Universal education needs to be free for everyone. 


3. Testing on animals should be eliminated because it does not produce the benefits it promises, it is a technique that is not ethical, and it is socially unacceptable because there are viable alternatives. 



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