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Inferences: SAT Reading and Writing notes
These questions give you a short passage that ends in a blank and ask which choice most logically completes it, using only what the passage has set up.
Study it with worked examples and 8 practice questionsPractise Inferences questions
What this topic tests
Every Inferences question looks the same: a short passage ends with a blank, and the question asks 'Which choice most logically completes the text?' The passage lays out facts, a study or an argument step by step, and the blank is the final step. Your job is to work out where the reasoning was heading.
An inference here is not a wild guess. It is the conclusion that must be true, or is very likely true, given what you've read. The right answer often feels a little plain, because it simply connects the dots. Wrong answers tend to be more exciting: they go further than the evidence, bring in a new topic, or turn the logic around.
The sentence with the blank is your best clue. Phrases like 'suggests that', 'if... then', 'however', 'casting doubt on' and 'because' tell you what kind of reasoning step you are finishing. More than half of these questions (37 of the 68) are rated Hard, so a steady method pays off.
Key ideas
- Read the whole passage, then reread the sentence with the blank and ask: what job does this blank do?
- Predict the ending in your own words before you look at the choices.
- The right answer uses only information from the passage. If a choice needs an outside fact or a new topic, it is wrong.
- Be wary of extreme words such as must, always, never, only, necessarily and best. Passages usually support may, likely or some.
- Check the direction. Many wrong answers say the opposite of what the evidence shows, or mix up which group did what.
- When a passage gives a general rule and then a specific case, the answer applies the rule to that case.
- When the blank follows 'casting doubt on the idea that', the answer is the idea being challenged, not the new conclusion.
The 4 kinds of Inferences question
Sorted from every Inferences question in the site's bank: each kind keeps coming up, and has a method that works every time.
1. What the evidence suggests
How to spot it. The passage describes a study, an observation or a set of facts, and the blank comes after words like 'This finding suggests that', 'Taken together, these findings suggest', 'the researchers concluded that', 'it can be inferred that' or 'it seems that'.
How to answer it:
- List the key facts or results, especially the last one or two before the blank.
- Ask what those facts show when you put them together, and say it in one short sentence of your own.
- Compare the choices with your sentence. Cross out any that bring in new topics, compare things the passage never compares, or use stronger words than the evidence allows.
- Pick the choice that follows from the facts and claims no more than they show.
The trap. The classic trap goes too far. It turns may into must, treats one study as proof about everything, or credits one cause when the study changed two things at once. If a choice would need another experiment to prove it, it is not the answer.
2. Apply a rule to predict
How to spot it. The passage sets up a general rule, theory or expectation, then gives a specific case and asks what should happen. Look for 'if... then', 'according to [someone]'s logic', 'anticipated that', 'would likely', 'should' or 'will' near the blank.
How to answer it:
- Write the rule in simple cause-and-effect form: when A happens, B follows.
- Identify the specific case in the last sentence and note every condition it includes.
- Apply the rule to each condition, step by step, and say what the result should be.
- Pick the choice that matches your result for every condition, not just one.
The trap. Wrong choices use the rule only halfway, for example handling one condition of an experiment and forgetting the other. Others swap in a result the rule never talks about, or answer a different question than the one the rule covers.
3. New evidence challenges an accepted idea
How to spot it. The passage first describes a common belief, a long-held theory or one side of a debate, then turns with however, but or recently to new evidence or a counterargument. The blank asks what that evidence suggests instead, or which idea it 'casts doubt on'.
How to answer it:
- Identify the accepted idea and state it in a few words.
- Identify the new evidence and decide exactly which part of the accepted idea it conflicts with.
- Read the wording before the blank. If it says 'casting doubt on the idea that', the answer is the old idea. If it says 'suggests that', the answer is what the new evidence points to.
- Pick the choice that does that job and stays within what the new evidence shows.
The trap. The biggest trap is answering the wrong job. When the blank asks what is being doubted, a choice that states the new conclusion sounds right but is backwards. Also avoid choices that throw out the old idea completely when the evidence only weakens one part of it.
4. Explain why, or name the link
How to spot it. The blank finishes a reason or a connection. Look for 'because', 'since... means that', 'replaced by technology that', 'linked in that', 'serves to', 'in this way' or 'there is a disparity between'. The passage gives you all the pieces, and you have to say how they fit together.
How to answer it:
- Work out what the blank must supply: a reason, a fix for a problem, a shared feature, or the point of an example.
- Find the facts that lead to it, such as a weakness, a goal, or two things described side by side.
- Connect them in one sentence of your own, for example: the old device had weakness X, so its replacement must not have X.
- Pick the choice that matches your connection and uses only ideas from the passage.
The trap. Wrong answers offer a reason that sounds sensible in real life but isn't set up by the passage, such as cost, popularity or ease of use when the text only talked about weather and daylight. Stick to the specific problem or link the passage actually describes.
Practise Inferences
On One for All SAT every question has a step-by-step solution, and the notes have worked examples of each kind of question, then practice questions you can check as you go. It's free, and there's nothing to sign up for.