Main Reason for Writing — Identify the main reason the...

SECTION 1

Why Does Author's Purpose Matter?

Every time someone writes something — a news article, a novel, a science report — they have a reason for writing it. We call this the author's purpose (the main reason the author created that piece of writing). Understanding author's purpose is one of the oldest and most important skills in reading. People have been thinking about why writers write for thousands of years.

350 BCE

Aristotle's Rhetoric

The Greek philosopher Aristotle taught that speakers and writers always have a goal: to persuade, to inform, or to entertain their audience.

1900s

Reading Comprehension in Schools

Schools began teaching students to ask "Why did the author write this?" as a core reading skill. Standardized tests started including purpose questions.

1970s

The PIE Framework

Teachers developed the PIE acronym — Persuade, Inform, Entertain — to help students remember the three main author purposes.

Today

SHSAT & Modern Testing

The SHSAT regularly asks you to identify the main reason an author wrote a passage. It is one of the most common question types on the exam.

Here is the big question this lesson answers: When you read a passage on the SHSAT, how do you figure out the main reason the author wrote it? By the end of this lesson, you will have a clear strategy to answer that question every time.

SECTION 2

Core Principles of Author's Purpose

Before you can identify the main reason for writing, you need to understand the basic categories of purpose. Almost every passage you read on the SHSAT fits into one of three big categories. Let's explore them.

To Inform

The author wants to teach you something or share facts. Think of textbooks, news articles, and encyclopedia entries. The tone is neutral and factual.

To Persuade

The author wants to convince you to believe something or take action. Think of editorials, advertisements, and speeches. The tone is opinionated and passionate.

To Entertain

The author wants to amuse you or tell a good story. Think of novels, poems, and humorous essays. The tone is creative and engaging.

To Describe / Explain

Sometimes the purpose is more specific: the author wants to explain how something works or describe an experience. This overlaps with informing but focuses on clarity and detail.

Main vs. Secondary Purpose

A passage can have more than one purpose. A story might entertain AND teach a lesson. The SHSAT asks for the MAIN reason — the biggest, most important one.

✦ KEY TAKEAWAY

Think of an author like a chef. A chef might make a dish to feed you (inform), to win a cooking contest (persuade), or to make you smile with a fun dessert (entertain). The main reason is the chef's biggest goal — even if the dish does a little of everything.

SECTION 3

Seeing Author's Purpose in Action

The diagram below shows the three main author purposes and the clue words and features that help you identify each one. When you read a passage, look for these signals to figure out the author's main reason for writing.

This diagram shows the three main types of author's purpose. Each box lists clue words and tone characteristics to help you tell them apart. The question at the bottom is the one you should always ask yourself when reading a passage.

Notice how each purpose has a different tone (the feeling or attitude you sense in the writing). Informative writing sounds calm and neutral. Persuasive writing sounds strong and opinionated. Entertaining writing sounds creative and engaging. Tone is one of your best clues.

SECTION 4

How to Identify the Main Reason for Writing

On the SHSAT, you won't just see a passage labeled "persuasive" or "informative." You have to figure it out yourself. Here is a step-by-step method you can use every time.

The 4-Step Purpose Check

Step 1 — Read the whole passage first. Don't try to answer the question after reading just the first paragraph. The main purpose often becomes clear at the end.
Step 2 — Ask: What is the overall topic? Summarize the passage in one sentence. This helps you focus on the big picture instead of small details.
Step 3 — Ask: What does the author want me to do, think, or feel? If the author wants you to learn facts → inform. If the author wants you to agree → persuade. If the author wants you to enjoy a story → entertain.
Step 4 — Check the answer choices. Eliminate choices that describe only a detail or a secondary purpose. The correct answer matches the WHOLE passage, not just one paragraph.

💡 SHSAT TIP

On the SHSAT, the question might not use the exact words "main reason for writing." It might say: "The author wrote this passage mainly to…" or "The primary purpose of this passage is to…" These all mean the same thing.

A common trick on the SHSAT is to include an answer choice that is true but too specific. For example, if a passage about ocean animals explains how dolphins communicate, an answer choice might say "to explain how dolphins use clicks." That's a detail, not the main reason. The main reason might be "to inform readers about ocean animal communication." Always pick the answer that covers the whole passage, not just one part.

SECTION 5

Clue Words and Signal Phrases

Authors leave clues in their writing that reveal their purpose. We call these signal phrases (words or phrases that hint at what the author is trying to do). The diagram below organizes common signal phrases by purpose.

This map groups common signal phrases by purpose. When you spot phrases like these in a passage, they point you toward the author's main reason for writing. The badges on the right (FACT, OPINION, STORY, HOW) summarize each purpose in one word.

Common SHSAT answer choice wording matched with each author's purpose.

Purpose	What You'll Notice	Common SHSAT Answer Wording
Inform	Facts, dates, statistics, definitions, neutral tone	"to explain…" "to describe…" "to present information about…"
Persuade	Opinions, strong words, calls to action, one-sided arguments	"to argue that…" "to convince readers that…" "to urge…"
Entertain	Characters, plot, dialogue, vivid descriptions, humor	"to tell the story of…" "to share an experience…" "to narrate…"
Explain	Step-by-step process, cause and effect, examples	"to show how…" "to illustrate…" "to clarify…"

SECTION 6

Worked Example — Finding the Main Reason

Let's walk through a short sample passage together, just like you would on the SHSAT. Read the passage, then follow the steps.

📖 SAMPLE PASSAGE

Every year, millions of monarch butterflies travel up to 3,000 miles from Canada and the United States to the mountains of central Mexico. Scientists have studied this migration for decades. They discovered that monarchs use the position of the sun and Earth's magnetic field to navigate. Recently, however, logging and climate change have destroyed large areas of the butterflies' winter habitat. Conservation groups are now working to protect the forests where monarchs spend the winter.

Question: The author wrote this passage mainly to —

(A) persuade readers to donate money to conservation groups
(B) inform readers about the monarch butterfly migration and threats to it
(C) entertain readers with a story about butterflies
(D) explain how scientists use magnetic fields to track butterflies

Step-by-Step Solution

Step 1 — Read the whole passageWe read the entire passage. It talks about monarch migration, how they navigate, threats to their habitat, and conservation efforts.

Step 2 — Summarize the topic in one sentenceThe passage is about monarch butterfly migration and the dangers it faces.

Topic: monarch butterfly migration and its threats

Step 3 — What does the author want me to do, think, or feel?The passage mostly gives us facts: distances, scientific findings, and what conservation groups are doing. It does not ask the reader to do anything or take a side. The tone is neutral and factual. This points to informing.

Purpose: to inform

Step 4 — Eliminate wrong answer choices(A) is wrong because the passage never asks readers to donate or take action. (C) is wrong because the passage is factual, not a creative story. (D) is too specific — it only mentions one detail. (B) matches the whole passage: it informs readers about the migration AND the threats.

Correct Answer: (B)

SECTION 7

Common Traps & How to Avoid Them

The SHSAT test-makers design wrong answer choices that look tempting. Here are the most common traps and how to beat them.

Four common SHSAT trap answer types for author's purpose questions.

Trap Type	What It Looks Like	How to Beat It
Too Specific	The answer is true but only covers one paragraph or one detail.	Ask: "Does this cover the WHOLE passage?" If not, it's a detail, not the main reason.
Too Broad	The answer is so general it could apply to almost any passage.	Ask: "Is this specific enough to match THIS passage?" If it's vague, keep looking.
Wrong Purpose	The answer says "to persuade" when the passage is actually informative.	Check the tone. Does the author express opinions and call for action, or just share facts?
Secondary Purpose	The answer describes something the author does, but it's not the MAIN reason.	Ask: "Is this the #1 biggest goal, or just something the author does along the way?"

✦ KEY TAKEAWAY

Think of finding the main reason like choosing the title of a movie. A movie about a kid learning to play basketball might have a funny scene with a dog, but you wouldn't title the movie "The Dog Scene." The title has to capture the whole story. The main reason for writing captures the whole passage, not one small part.

SECTION 8

Beyond the Basics — Harder SHSAT Purpose Questions

Some SHSAT passages make it trickier to find the purpose because the author does more than one thing. For example, a passage might tell a personal story about a scientist AND inform you about her discovery. In cases like this, you need to decide which purpose is most important to the passage as a whole.

How basic and advanced approaches to author's purpose compare on harder SHSAT questions.

Situation	Basic Approach	Advanced SHSAT Approach
Passage has one clear purpose	Identify the purpose directly using clue words and tone.	Same — straightforward.
Passage mixes fact and opinion	Decide if the passage is mostly facts or mostly opinions.	Look at the conclusion. If the ending makes a claim or call to action, the main purpose is to persuade.
Passage tells a story AND teaches a lesson	Ask which element takes up more of the passage.	If the story serves the lesson, the purpose is to inform or explain. If the lesson serves the story, the purpose is to entertain or narrate.
Answer choices use unfamiliar wording	Look for keywords like "argue," "explain," "narrate."	Translate each answer choice into your own words. Match your one-sentence summary to the simplest restatement.

As you move toward high school, you'll encounter even more complex texts where the author's purpose shifts between paragraphs. For now, remember that the SHSAT wants you to find the single most important reason the author wrote the passage. Keep your focus on the big picture.

SECTION 9

Practice Problems

PROBLEM 1 — CONCEPTUAL

A newspaper article gives the date, location, and details of a local park cleanup event. It includes quotes from volunteers but does not express any opinion about whether readers should attend. What is the author's main purpose?

PROBLEM 2 — BASIC

Read this opening line: "Cities across the country must invest more money in public transportation, or traffic congestion will only get worse." What is the most likely main purpose of a passage that begins this way? (A) to inform readers about traffic statistics (B) to persuade readers that cities need better public transportation (C) to entertain readers with a story about commuters (D) to explain how buses work

PROBLEM 3 — INTERMEDIATE

A passage describes how honeybees communicate the location of flowers through a "waggle dance." It explains the steps of the dance and how other bees interpret the movements. The passage ends by saying, "This remarkable system allows a single bee to guide the entire hive to a food source miles away." What is the main reason the author wrote this passage? (A) to argue that honeybees are more intelligent than other insects (B) to entertain readers with a funny story about dancing bees (C) to explain how honeybees use a waggle dance to communicate (D) to warn readers about the dangers bees face from pesticides

PROBLEM 4 — APPLIED

A passage begins by telling the true story of a 12-year-old girl who started a recycling program at her school. It describes the challenges she faced and how she convinced the principal to support her. The last paragraph shares statistics showing that student-led recycling programs have reduced waste by 30% in schools across the state. What is the main reason the author wrote this passage? (A) to entertain readers with the girl's funny experiences at school (B) to inform readers about one student's successful recycling effort and its wider impact (C) to persuade readers to start their own recycling programs (D) to describe what it's like to be a student in middle school

PROBLEM 5 — CRITICAL THINKING

A passage about space exploration begins with exciting descriptions of astronauts floating in zero gravity. The middle section explains how NASA selects and trains astronauts. The final paragraph states, "Without continued government funding, these incredible missions will come to an end, and humanity will lose its chance to explore beyond Earth." A student says the main purpose is to entertain because the passage uses vivid, exciting language. Do you agree or disagree? Explain your reasoning using evidence from the passage.

SUMMARY

Lesson Summary

The main reason for writing is the author's biggest goal for the entire passage. On the SHSAT, the three most common purposes are to inform (share facts), to persuade (change your mind), and to entertain (tell a story or amuse). You can also see purposes like to explain or to describe.

Use the 4-Step Purpose Check: (1) read the whole passage, (2) summarize the topic, (3) ask what the author wants you to do, think, or feel, and (4) eliminate wrong answer choices. Watch out for trap answers that are too specific, too broad, or describe a secondary purpose. Look for signal phrases and tone to guide you, and always choose the answer that matches the whole passage, not just one part.