Central ideas and details

The companion to purpose questions. Which choice best states the main idea of the text? — and the detail questions that ask what the text says about one specific thing.

#Main idea

The main idea is the claim the rest of the passage exists to support. Two quick locators:

• The sentence everything else explains. Read the passage and ask which single sentence, if you kept only it, would still tell you what the author thinks.
• The turn. If there's a but, however, or yet, the main idea is almost always on its far side. What comes before a however is setup.

Predict in one sentence before looking. Then eliminate on scope: a choice that covers more than the passage or less than the passage is wrong even if every word in it is true.

#The two failure modes

Too narrow — a real detail from the passage, promoted to main idea. Tempting because you can find it in the text.

Too broad — the topic rather than the claim. "The text discusses migration patterns" is a topic. "Migration patterns shift faster than models predict" is a claim. Main-idea answers are claims.

#Detail questions

According to the text, X is... These are open-book and should be fast — 30 to 45 seconds. The rule: find the line, and answer from the line. Not from your memory of the passage thirty seconds ago, which will have smoothed the details.

The trap is the answer that's true of the passage generally but not of the specific thing asked about. Locate the words from the stem in the passage, read that sentence and the one after it, and answer from there.

#Quantifiers decide these

Watch every all, most, some, few, never, always, often, can, must, may. A choice that says a study showed X causes Y when the passage said it's associated with Y is wrong, and that's a one-word difference. Similarly all versus most, proves versus suggests, will versus may.

When two choices survive, the difference is nearly always one of these words. Find it, go back to the text, and check which one the text supports.