The topic is the subject matter treated in a passage. This may seem obvious, but there’s a bit of a twist, as you’ll soon see. Read the passage below and write down what you think the topic is in the space provided:

The topic is not necessarily so straightforward in an RP. In order to correctly identify the topic, you need to consider a passage’s scope. A correctly identified topic has the appropriate scope—neither too broad nor too narrow. Think of scope as the breadth of the topic covered in the passage. In the passage above, the topic is the themes of Verdi’s operas. The chart below shows different ways of being outside the scope of this passage.

Note how scope can be either too broad, too narrow, or just plain off-topic. One way to think of scope is to compare it to the frame of a photograph. If you want to photograph, say, your house, you’ll certainly want something in between a satellite photo of the entire Earth and an electron micrograph of the wood on your front door! You’ll want just the front of the house with a little space on all sides to show a bit of the yard and trees. And you don’t want a picture of someone else’s house or of, say, the White House or the Empire State Building. That would be “off topic,” so to speak.

Another way to think of topic and scope is to pretend that you’re categorizing the passage for retrieval by an internet search engine. You want to get the minimum number of “hits” or “matches” without choosing a scope so small that your search will miss the article completely. The Verdi passage could be categorized under “European music,” but that would cover two thousand years of all types of popular and classical music for the entire continent. “Nineteenth-century European music” is more specific, but still includes every type of music from every European country. “Verdi’s music” is getting closer, but still doesn’t focus specifically on his operas. And the excessively narrow scopes focus on certain aspects of Verdi’s operas—the arias—that are mentioned but that are not the proper scope of the passage. Finally, “nineteenth-century Italian politics” is also mentioned, but we’re concerned with the relationship between Verdi’s operatic themes and nineteenth-century Italian politics, not with nineteenth-century Italian politics in and of itself.

Therefore, if you had to choose a categorization for a search engine that would retrieve this passage as quickly as possible, it would be the underlined one below.

The main idea of a passage is the central point that the author is making. Go back to the Verdi passage again: write down what you think the main idea of this passage is in the space below. Then, read our answer.

A text’s main idea encompasses more than the details—it’s the one phrase or sentence that covers the topic. Think of it this way: in a dresser drawer, you keep your socks, your underwear, and your t-shirts. The “main idea” of that drawer is not “socks” or “underwear” or “t-shirts”—it’s “undergarments.”

Therefore, the main idea is a clear expression of the topic and scope, along with the author’s particular take on that topic and scope. Here’s a comparison of the topic and main idea for the passage we’ve been using:

You’ll usually find one main idea item per long or paired RP.

Purpose refers to the author’s purpose. Why did he or she write this passage? What is the point he or she is trying to make? Take the Verdi example again: write the author’s purpose in the space provided below.

Whereas the main idea tells you what the author wrote, the purpose tells you why. Virtually all nonfiction passages contain an argument—an assertion backed up by evidence. (We’ll go over these terms shortly.) Even fiction passages contain purpose. An author can write fiction on any topic; what an author chooses to write about exposes the author’s purpose. If, for example, an author writes sympathetically about the hard times poor American farmers faced in the Great Depression, that author’s purpose is likely to raise awareness of the plight and dignity of those farmers and their families.

The following chart compares topic, main idea, and purpose for the passage we’ve been using.

Tone is often a difficult concept to grasp. It’s based both on a passage’s style and on the particular words used in the passage. The way an author uses language implies how the author was feeling at the time. Was she angry? Sad? Excited? Resigned? Depressed?

Read the Verdi passage once more, looking for clues about the passage’s tone. Then, write a description of the tone in the space provided below.

The author acknowledges that Verdi’s arias have garnered the most praise but argues that the political commentary is more impressive and important. What’s the tone of the following passage?

The tone is much harsher and more combative, isn’t it? This author is obviously a lot more annoyed by the current basis for Verdi’s fame. The two passages share the same topic, scope, and main idea. But the tone is radically different. The first passage had a relaxed tone; the author was suggesting another and better way to appreciate Verdi’s operas. The second passage is much angrier and more sarcastic. The author is ridiculing the ignorance of contemporary historians rather than merely suggesting an alternative viewpoint.

Theme is another difficult concept to grasp. Like the main idea, the theme can be described as the passage’s subject matter, but themes are usually deeper and more general than main ideas.

For example, here’s what we’ve already determined about the Verdi passage:

What theme does the author touch upon? One way of putting it is:

Themes are also important in fiction, because they allow readers to look for deeper meaning in a story. The chart below provides some plots or subject matter along with some classic themes. The point is not to memorize these themes, but to use this chart to begin to understand the difference between topic, main idea, and theme.

Themes don’t have to be as grandiose as the ones listed in the chart. They can be as mundane as proverbs. For example, the theme of this book is: the more you understand the structure and content of RPs, the more likely you are to maximize your potential on that part of the SAT.

Logic is as important in fiction as it is in nonfiction. Certain basic rules, such as cause and effect, need to be incorporated to avoid confusion. The argument or plot in an RP will flow logically, and you’ll be asked to identify this flow, and perhaps add to it.

Logical flow is most obviously transmitted by signpost words, which often link paragraphs. English has many such guide words and phrases. No single SAT test will include them all, but here’s a handy list of some common ones:

Sentence structure, too, can show logical flow. How clauses and phrases are positioned and the punctuation used to connect them generates the flow that all good writing must have. We’ll point this out in the passage you’ll work on later in the book. For now, let’s take a look at some key logical terms.

A fact is an objective statement about reality, such as “The Earth is a sphere” or “Charlemagne was a Holy Roman Emperor.” Facts can be interpreted in various ways and have various implications.

Many RP items ask you to find a particular fact in the passage. Other items will ask you to draw out a likely implication from a fact or set of facts; still others will ask you how the author might react to a new fact not in the author’s passage.

Assumptions are facts or assertions that are taken for granted and usually unstated. Readers reach conclusions through a combination of facts and assumptions. Identifying underlying assumptions is crucial in RPs.

For example, if an author writes: “The best way to stimulate the economy is by reducing personal income taxes,” there are some hidden assumptions to be uncovered. Assumptions aren’t necessarily true or false, but the SAT wants to ensure that students can identify them.

We could go on, but you get the idea. Everyone’s writing (and thinking) is littered with hidden assumptions.

We infer all the time. Here’s an example:

An inference is best understood as an unobserved fact that one believes must be true given other observed facts: if there was no snow when I went to bed and there’s a ton of snow this morning, you can bet the farm that it snowed overnight.

Some inferences are not as logically necessary as the snow example. They are merely statistically possible or logically probable. For example:

Well, that might be the case. It’s plausible—the reasoning used to infer that student complaints led to the policy change makes sense. But there are other possible reasons, each of which is based on a hidden assumption:

Many RP items will ask you to make an inference based on the information given in the passage. You’ll need to decide which inferences are valid and which are not. Proper inferences on the SAT tend to be closer to the snow example than to the dress code example—that is, more logically necessary than statistically probable.