# SAT Text Structure and Purpose: Method, Example | topin

SAT guidesText Structure and Purpose

Section

Reading and Writing, Craft and Structure domain

Count

Usually 2–3 per module, after Words in Context

Question forms

Main purpose, overall structure, function of an underlined sentence

Passages

Prose or poetry, 25–150 words, any subject

Time

About a minute each

## How it works

You read a short passage, sometimes with one sentence underlined, and choose the answer that describes what the text does rather than what it says. Choices are written in abstract language, such as "presents a claim and then qualifies it". Harder items have two-part answers where one half is accurate and the other is not.

## Worked example

For much of the nineteenth century, lighthouse keepers were pictured as solitary figures cut off from the world. Logbooks kept at stations on the Great Lakes complicate that picture. Keepers recorded frequent visits from fishing crews and weekly mail deliveries, and at several stations children rowed to the mainland for school. Isolation, the logbooks suggest, was often a matter of season rather than a permanent condition: it set in when ice closed the lakes each winter. Which choice best describes the overall structure of the text?

1. AIt presents a common view, offers evidence that complicates it, and proposes a narrower version of that view.
2. BIt describes a historical occupation, then argues that the occupation was more dangerous than is usually thought.
3. CIt compares two kinds of historical records and concludes that one is more reliable than the other.
4. DIt outlines a disagreement between historians and explains why the disagreement remains unresolved.
Show the answer

A

Label each sentence: sentence 1 gives the common picture (keepers were isolated), sentences 2 and 3 give evidence against it (visitors, mail, school), and the last sentence keeps part of the view but narrows it (isolated in winter only). A matches all three moves. B introduces danger, which the passage never mentions. C invents a comparison of two kinds of record; there is only one. D invents a debate between historians.

## A method for Text Structure and Purpose

1. 1  
### Read the question first  
Know whether you need the purpose of the whole text, its structure, or the function of one underlined sentence, because each needs a different focus.
2. 2  
### Label each sentence  
In a few words, note what each sentence does: introduces a view, gives an example, contrasts, qualifies, concludes. This turns the passage into a simple map you can match to a choice.
3. 3  
### Predict the answer in your own words  
Join your labels into one line, such as "common view, evidence against, narrower view". For an underlined sentence, ask how the passage would change if it were removed.
4. 4  
### Check every part of each choice  
Split each choice at words such as and, then or before, and check each half against the passage. One wrong half makes the whole choice wrong.

## Traps to avoid

* A two-part answer where the first half is right and the second describes something the passage never does.
* A choice that summarises the content correctly but does not describe the structure or purpose asked for.
* Extreme verbs such as refutes or dismisses when the passage only qualifies or complicates a view.
* For underlined sentences, describing what the sentence says instead of what it does for the passage.

## Text Structure and Purpose FAQs

What is the difference between main purpose and main idea on the SAT?

Main purpose asks why the author wrote the text, described as an action such as to explain, to challenge or to describe. Main idea, a Central Ideas question, asks what the text says.

How do I answer underlined-sentence questions?

Ask what the passage would lose without the sentence. If it supplies an example for the claim before it, the answer will say it illustrates or supports that claim.

Are poems used in Text Structure and Purpose?

Sometimes. Treat a poem the same way: label what each part does, such as describing a scene, then shifting to a memory, and match that sequence.

## Try Text Structure and Purpose under real timing

Your first full-length SAT mock is free, with every section included.

[Take the free mock ](/sat/login)