Every grammar rule the digital SAT recycles, on one printable page, plus the tell that reveals which rule a question is testing. The questions never come labeled, so this sheet labels them for you.
By the Forge team·Jul 3, 2026·Reference
Short version: grammar questions don't announce themselves. Look at what changes across the four choices (a verb, a pronoun, an intro phrase, a list) and that tells you which rule is in play and which trap to watch for. Start with the decoder below.
The move: cross out everything between the subject and the verb, then check the match.
Ignore prepositional phrases and asides: The box of old ornaments sits (not sit) on the shelf.
Collective nouns (team, family, committee) are singular.
Indefinite pronouns (each, every, everyone, neither, either) are singular.
With neither/nor and either/or, the verb matches the closest subject.
Pronouns
Rule
What to check
Agreement
A pronoun matches its noun in number. A singular company takes its, not their.
Ambiguity
If a pronoun could point to two nouns, replace it with the specific noun.
its vs. it's
it's = "it is." its = possessive. Always.
their / they're / there
possessive / "they are" / a place. The test swaps these on purpose.
Modifiers
The rule: an opening phrase describes the noun right after the comma.
Dangling modifier = that noun is wrong or missing: "After hiking for hours, the summit came into view." The summit didn't hike.
Fix: ask "who did the action?" and put that noun right after the comma: "After hiking for hours, we saw the summit."
Parallel structure
Situation
The rule
Lists
Every item wears the same grammatical form: hiring, investing, and overhauling.
not only… but also
Whatever follows not only matches whatever follows but also.
Comparisons
Compare like things: "than those of the sales team," not "than the sales team."
Verb tense
Keep tense consistent with the timeline the passage has already established. Don't shift from past to present without a reason in the sentence. When only the tense changes across the choices, the answer is the one that matches the verbs around it.
The traps the test repeats
Trap
The fix
Verb agrees with the nearest noun
It agrees with the subject, which the test hides behind phrases. Cross them out.
"their" for a singular noun
A company, team, or committee is singular: its.
Ambiguous he / they / it
Name the noun instead of the pronoun.
Dangling modifier
Put the real subject right after the opening comma.
Faulty parallelism / illogical comparison
Match the forms; compare like to like.
None of these reward instinct. They reward a fast diagnosis and the right tool, which is why they are among the most recoverable points on the test once you drill them. Forge can show you whether grammar is a steady strength or a quiet leak, and which specific rule keeps catching you, so your practice goes to the one actually costing you points instead of all of them at once.
Find the one grammar rule that keeps catching you.