20 SAT Grammar Rules

If you are scheduled to take the SAT this year, there is a good chance you are entering the wide world of SAT prep. Initial preparation might include determining what constitutes a good SAT score and experimenting with our interactive SAT Score Calculator. Remember that a “good” SAT score depends on you and your goals. Perusing the SAT score ranges of accepted applicants at various institutions will help you identify your target score. Aiming for a target score that matches your aspirations can eliminate much of the stress surrounding the SAT. Moreover, remember that your SAT score is just one aspect of your application—one considered alongside your GPA, essays, etc. (Continue for SAT Grammar Rules).

Once you’ve outlined your individualized SAT goals, you’ll want to begin preparing for the various components of the test. As a reminder, The digital SAT is composed of two timed sections, each split into two equal-length modules:

SAT Grammar Rules (Continued)

1. Reading and Writing (64 minutes, or 32 minutes for each module)
2. Math (70 minutes, or 35 minutes for each module)

We’ll focus here on the Reading and Writing section, which tests your knowledge of grammar and writing style. Specifically, the questions fall into two main types:

• Those where you improve the expression of ideas
• Those where you have to recognize and correct errors in sentence structure, grammar, usage, and punctuation

With the second type, you are being tested on “Standard English Conventions.” That means that the questions focus on recognizing and correcting grammar, usage, and mechanics problems in passages. Mastering common grammatical rules will set up to perform well on these questions, and on the Reading and Writing section as a whole.

As a bonus, learning these rules will strengthen your own reading comprehension and writing skills—allowing you to perform better on other tests (AP exams, for instance), in reading and writing-focused classes (both in high school and beyond), and—well—in life!

20 SAT Grammar Rules – Cheat Sheet

These rules are divided into two types: 1) Syntax and Mechanics and 2) Punctuation.

SAT Grammar Rules – Syntax and Mechanics

1) Subject and Verb Must Agree

Subjects and verbs must agree in number. If the subject is singular (one), use a singular verb. If the subject is plural (more than one), use a plural verb.

Incorrect: The dog chase the ball.

Correct: The dog chases the ball.

TIP: If the verb is in the present tense and the singular subject is in the third person, the verb usually ends in “s.”

2) Collective Nouns are Singular

While subject-verb agreement may seem easy, collective nouns complicate matters. Collective nouns refer to multiple individuals but act as singular subjects. Examples: group, crowd, herd, committee, etc.

Incorrect: The crowd demand bread.

Correct: The crowd demands bread.

TIP: Multiple groups (crowds, groups, herds, committees, etc.) require plural verbs. For example:

Incorrect: The crowds demands bread.

Correct: The crowds demand bread.

SAT Grammar Rules (Continued)

3) Prepositional Phrases Do Not Make a Subject Singular or Plural

Prepositional phrases (groups of words containing prepositions) link nouns and pronouns to the other words in a sentence, but have no effect on whether the subject is singular or plural.

Incorrect: The herd of cattle graze in the meadow.

Correct: The herd of cattle grazes in the meadow.

TIP: Crossing out the prepositional phrase can help you identify the subject, as you can see with the above example:

Incorrect: The herd of cattle graze in the meadow.

Correct: The herd of cattle grazes in the meadow.

4) Modifiers Must be Next to the Word, Phrase, or Clause they’re Modifying

Modifiers are words, phrases, or clauses that clarify or describe another word, phrase, or clause. Misplaced or dangling modifiers lead to sentences that are ambiguous or awkward. Hence, whenever a modifier appears, it must be next to the word, phrase, or clause it is modifying.

Incorrect: They adopted a puppy for my sister they call Scruffy.

Correct: They adopted a puppy they call Scruffy for my sister.

As you can see, in the incorrect sentence it seems that the sister is called Scruffy. While not impossible, the context of the sentence indicates that the word being modified by “they call Scruffy” is “puppy,” not “sister.”

TIP: Often, correcting a misplaced or dangling modifier requires restructuring the sentence and adding words and/or punctuation. For example:

Incorrect: The parents announced their plan to adopt a puppy during the family meeting.

Correct: During the family meeting, the parents announced their plan to adopt a puppy.

In the incorrect usage, it is not clear what the modifying phrase (during the family meeting) is modifying. Is the puppy going to be adopted during the meeting or is that merely when the parents announced the plan? The correct version makes it clear that “during the family meeting” is modifying “the parents.” It answers the question of “when” the parents made the announcement, not when the puppy was adopted.

SAT Grammar Rules (Continued)

5) Pronouns Must Have a Clear Referent and Agree in Number

Pronouns are words that take the place of nouns or noun phrases and whose referents are named or understood in context. Moreover, a singular pronoun (I, me, she, her, it, etc.) must refer to a singular noun and a plural pronoun (we, us, they, etc.) must refer to a plural noun.

Incorrect: Katie and Scruffy were playing when she got thirsty and drank some water.

Correct: Katie and Scruffy were playing when Scruffy got thirsty and drank some water.

As “she” can refer to either Katie or Scruffy, the referent in the incorrect version is unclear.

Incorrect: The scores of the students in Sal’s class were higher than that of Pat’s class.

Correct: The scores of the students in Sal’s class were higher than those of Pat’s class.

In the incorrect version, the pronoun “that” refers to “scores.” Since “scores” are plural, the pronoun must also be plural (“those,” as in the correct version). The above example shows how prepositional phrases have no effect on whether the pronoun is singular or plural.

TIP: While conventions around the singular use of “they,” “them,” and “their” are changing, for the purposes of the SAT consider these pronouns plural. For example:

Incorrect: Jane took off their coat.

Correct: Jane took off her coat.

6) Correlative Conjunctions Always Come in Pairs

Correlative conjunctions are conjunctions used to show how two words or phrases in a sentence relate to each other as equal elements. The most common correlative conjunction pairs include:

• Either/or
• Neither/nor
• Such/that
• Whether/or
• Not only/but also
• Both/and
• As many/as
• Rather/than
• No sooner/than

Examples:

Scruffy would rather go to the park than the vet.

Katie loves the music of both Taylor Swift and Beyonce.

TIP: Because the first correlative conjunction requires its pair word to be complete, flag the word when you see it and locate its partner word to determine if the sentence is correct and complete.

7) Keep Verb Tenses Consistent

Verbs should remain consistent in tense or form throughout a sentence.

Incorrect: Scruffy loves squeaky toys and carried her favorite everywhere.

Correct: Scruffy loves squeaky toys and carries her favorite everywhere.

TIP: Verb tenses of surrounding sentences can provide context clues and help you avoid consistency issues. For example:

Incorrect: Scruffy loves squeaky toys. She carried her favorite squeaky ball everywhere.

Correct: Scruffy loves squeaky toys. She carries her favorite squeaky ball everywhere. 

SAT Grammar Rules (Continued)

8) Parallel Ideas Must be Presented in Parallel Grammatical Form

In a sentence, all verb tenses and grammatical structures must remain parallel.

Incorrect: Scruffy enjoys going to the park, lounging on her dog bed, and to play with her squeaky toy.

Correct: Scruffy enjoys going to the park, lounging on her dog bed, and playing with her squeaky toy.

In the incorrect version, “going” and “lounging” are gerunds (verbs functioning as nouns), whereas “to play” is an infinitive. In order to achieve parallelism, “to play” must be changed to “playing” to repeat the gerund pattern.

Here’s another example:

Incorrect: For breakfast the horses like hay and to chomp on oats.

Correct: For breakfast the horses like hay and oats.

Also Correct: For breakfast the horses like to munch on hay and chomp on oats.

In the incorrect version, “hay” is a noun, but “to chomp” is a verb. To make the structure parallel you either need two nouns or two verbs + two nouns.

TIP: A lack of parallelism can also occur when noun numbers don’t agree, parts of speech don’t match, or the ideas discussed in a sentence don’t relate to one another.

9) Beware the Run-On Sentence

To understand run-on sentences, you must first understand compound sentences. A compound sentence has more than one independent clause—meaning two subjects and two verbs. If independent clauses aren’t joined together correctly, you’ll end up with a run-on sentence.

Incorrect: The puppy will learn to sit eventually you need to keep taking her to puppy class.

Here we have two independent clauses (“The puppy will learn to sit eventually” and “you need to keep taking her to puppy class”) that aren’t joined together correctly. Run-on sentences can be fixed or prevented by:

• Joining the independent clauses with a comma and a coordinating conjunction (for, and, nor, but, or, yet, so).

Correct: The puppy will learn to sit eventually, but you need to keep taking her to puppy class.

• Or dividing the clauses into two sentences.
  

Correct: The puppy will learn to sit eventually. You need to keep taking her to puppy class.

• Or inserting a semicolon between the two clauses (for more on semicolons, see below).Correct: The puppy will learn to sit eventually; you need to keep taking her to puppy class.

TIP: We tend to think of run-on sentences as being long and wordy, and they can be! However, shorter sentences can also be classified as run-ons if the independent clauses aren’t joined correctly.

10) A Sentence Fragment Can be Fixed by Adding the Missing Part

A sentence fragment is an incomplete sentence used in place of a complete sentence. Typically, a sentence fragment lacks either the subject or predicate required to make it an independent clause.

Incorrect: Scruffy sleeping on her beloved dog bed.

Correct: Scruffy slept on her beloved dog bed.

TIP: We tend to think of sentence fragments as short (just as we tend to think of run-on sentences as long), but this isn’t always the case. The following, for example, while lengthy, is a sentence fragment:

The adorable puppy, with her fluffy fur and big brown eyes, standing against the backdrop of the expansive park, surrounded by dogs of all kinds, waiting for Katie to stop talking to her friend and throw the ball. Here we have a heavily-modified subject, but the sentence lacks a predicate.

SAT Grammar Rules (Continued)

11) Know the Difference Between Transitive and Intransitive Verbs

Unfortunately, identifying sentence fragments becomes trickier when dealing with transitive vs. intransitive verbs:

• Transitive verbs are verbs that require a direct object
• Intransitive verbs are verbs that do not require a direct object.

That is, an intransitive verb will make sense without an object, whereas a transitive verb requires an object to express a complete thought.

Incorrect: Scruffy carries.

Correct: Scruffy carries her toy.

The incorrect version contains a subject and a verb, yes, but remains incomplete due to its use of a transitive verb.

TIP: To remember the difference between transitive and intransitive verbs, know that a transitive verb needs to transfer its action to something or someone.

12) Know Your Homophones!

Homophones are words that sound identical (or very similar), but have different meanings. Unfortunately, there’s no real trick to identifying homophones—you just need to memorize them. Some are more common than others, including:

• Your/you’re
• There/their/they’re
• Whose/who’s
• Its/it’s
• To/too/two
• Here/hear
• Affect/effect
• Weather/whether
• Passed/past
• Loose/lose

Incorrect: Katie through the ball for Scruffy.

Correct: Katie threw the ball for Scruffy.

TIP: SAT word choice questions typically refer to sentences that appear in longer passages. Although the example above may seem easy, during the test you may be skimming and/or in a rush and more likely to miss homophones.

13) Who vs. Whom, Who’s Vs. Whose, That vs. Which

While mastering general grammatical rules is important, it is also worth your time to focus on a few specific rules. Figure out which common grammar mistakes tend to stump you, and memorize the rules.

• Who vs. Whom: Who is the subject of a sentence, whereas whom is the object of a sentence.

Example: Who owns this toy?
Example: To whom should I give this squeaky toy?

SAT Grammar Cheat Sheet (Continued)

• Who’s vs. Whose: Who’s is a contraction of who is, whereas whose is the possessive form of who.

Example: Who’s the dog’s owner?
Example: Whose dog is this?

• That vs. Which: That introduces a clause that adds necessary information to a sentence, whereas which introduces a clause that adds detail but isn’t necessary to the overall meaning of the sentence.

Ex: The sandwich that has the homemade pickles is my favorite!
Example: This sandwich, which has homemade pickles, is delicious!

TIP: Not sure which rules to memorize? Peruse a few lists of specific grammar mistakes and take note of which ones you’d need to look up in order to explain to someone else.

SAT Grammar Rules – Punctuation

14) Surround Non-Restrictive Clauses and Appositives with Commas

Appropriate comma usage depends on understanding Restrictive vs. Non-Restrictive clauses:

• Restrictive clauses are necessary to the meaning of the sentence. That is, you cannot remove a restrictive clause from a sentence without changing the meaning of the sentence.

Example: Puppies who attend classes learn basic commands.

If you removed the clause “who attend classes,” the meaning of the sentence would change significantly.

• Non-Restrictive clauses are not essential to the meaning of the sentence.
  
  Example: Scruffy, who is very cute, learned basic commands during puppy classes.If you removed the clause “who is very cute,” you’d have less detail, but the overall meaning of the sentence would not change.

Restrictive clauses should not be surrounded by commas, whereas non-restrictive clauses should be surrounded by commas.

Like non-restrictive clauses, appositives (descriptive phrases that do not include a verb) can be removed without changing the meaning of the sentence, and should be surrounded by commas.

Example: Scruffy, a golden retriever puppy, learned basic commands during puppy classes. 

SUMMARY: If you can eliminate a clause or descriptive phrase without changing the meaning of the sentence, use commas to set the clause or phrase apart.

SAT Grammar Rules (Continued)

15) Commas Cannot Separate Two Independent Clauses

 Learning to recognize and correct comma splices is a foundational skill. A comma splice occurs when a comma is used to separate two complete thoughts.

Incorrect: My sister loves Taylor Swift, she dances to her music all the time.

Correct: My sister loves Taylor Swift, and she dances to her music all the time.

Also Correct: My sister loves Taylor Swift; she dances to her music all the time.

Also Correct: My sister loves Taylor Swift. She dances to her music all the time.

SUMMARY: If you can replace a comma with a period and end up with two complete sentences, you have a comma splice.

16) Semicolons Can Separate Two Independent Clauses

Unlike the comma, the magical semicolon can separate two independent clauses. Stylistically, a semicolon is used in place of a period to convey a close relationship between two complete thoughts.

Incorrect: Since my sister loves Taylor Swift; she drove four hours to attend her concert. Correct: My sister loves Taylor Swift; she drove four hours to attend her concert.

SUMMARY: If you can replace a semicolon with a period and end up with two complete sentences, the semicolon is being used correctly.

17) Colons Can Only Appear at the End of an Independent Clause

Colons can be used to introduce lists or explanations, but only if they come after a complete sentence.

Incorrect: Scruffy enjoys many activities like: going to the park, riding in the car, chewing her squeaky toys, and playing with Katie.

Correct: Scruffy enjoys many activities: going to the park, riding in the car, chewing her squeaky toys, and playing with Katie.

SUMMARY: If you replace the colon with a period, the first sentence should form a complete thought.

SAT Grammar Rules (Continued)

18) Em Dashes Separate Nonessential Elements from the Rest of the Sentence

First, make sure you know the difference between em dashes, en dashes, and hyphens.

The em dash is used to separate a group of words from the rest of the sentence. A single em dash be used instead of a pair of parentheses around material at the end of a sentence, or a pair of em dashes can replace a pair of commas. An em dash can also be used in lieu of a colon.

Examples:

After a moment of hesitation, Katie jumped into the pool—or, rather, belly-flopped into it.

Scruffy’s favorite ball—because of its green color—was difficult to spot in the grass.

Scruffy is afraid of two things—cats and thunder.  

SUMMARY: While the choice to use an em dash rather than another form of punctuation is a stylistic one, an em dash can only be used to separate out nonessential elements from a sentence.

19) Use Apostrophes Correctly to Form Possessives or Contractions

Don’t rely on “what looks right” when using apostrophes. Learn the rules instead!

• If a word is singular or plural but doesn’t end in “s,” then add an “s” after the apostrophe to form a possessive.

Examples: Scruffy’s favorite ball is green. The children’s room is green.

• If a word is plural and does end in “s,” then add an apostrophe after the “s” to form a possessive.

Example: The puppies’ owners were exhausted after an afternoon at the dog park.

• Contractions are formed when you combine two words. Apostrophes are used in place of any dropped letters. Examples include it’s (it is), don’t (do not), could’ve (could have), and isn’t (is not).

SUMMARY: Only use apostrophes for possessives or contractions. DO NOT use apostrophes to create plural nouns. For example, the plural of Tuesday is Tuesdays, not Tuesday’s. You would only use “Tuesday’s” to form a possessive, such as “Tuesday’s meeting.”

SAT Grammar Rules (Continued)

20) Punctuation Marks (Almost Always) Go Inside Quotation Marks

Quotation marks are used to show direct quotes or dialogue, or else to set words and passages apart from the rest of a text. When using a period, comma, or exclamation mark with quotation marks, place the punctuation inside the quotation marks.

Examples:

“Wow,” said Katie, “that green ball is really difficult to spot in the grass.”

“Come here, Scruffy!” shouted Katie.

Question marks are more complicated. If the question mark is part of the quote, it goes inside the quotation marks. If the question mark is not part of the quote, it goes outside the question marks.

Examples:

“Did you have fun?” she asked.

Did Scruffy just say “I love Taylor Swift”? Katie asked jokingly.

SUMMARY: With few exceptions, punctuation marks go inside quotation marks.

While this list of rules is far from exhaustive, it will help you prepare for the SAT. Remember that practice is key, and while these rules may seem simple in isolation, they can be more challenging to remember and follow during the test itself.