SAT / ACT Prep Online Guides and Tips

Strategies for Improving Sentences on SAT Writing


Improving sentences is the biggest subsection in SAT Writing. There are 49 total multiple choice questions on the SAT Writing section, and 25 of those are improving sentences questions. Arming yourself with specific strategies to answer these questions will be extremely beneficial to you and your SAT Writing score.

In this post, I’ll do the following:

  • Offer a general approach to use for answering sentence improvement questions.
  • Detail the most common errors and clues for locating them.
  • Show you how to correct the most common grammar errors.
  • Provide example questions.


General Approach to Improving Sentences

For each improving sentences question, you should follow the same general approach to help ensure that you have an efficient method to consistently select the correct answer. By following these steps, you'll become less likely to make careless mistakes and more likely to arrive at the right answer in a timely manner.


#1: Read the Sentence and Try to Identify Any Specific Errors in the Underlined Portion

When you first read through the sentence, attempt to locate specific errors based on your knowledge of the grammar rules that are tested on the SAT Writing section.


#2: Eliminate Obvious Wrong Answer Choices

Eliminate any choices that are clearly wrong. If an answer choice creates another grammatical error or does not address the error you identified in the original answer choice, then you can immediately eliminate that answer choice as an option.

Don't eliminate an answer choice solely because it sounds wrong. For all of the multiple choice SAT Writing questions, rely primarily on your knowledge of grammatical rules.


#3: If You Don't Notice Anything Wrong With the Original Sentence, Look at the Answer Choices to Determine if You Overlooked an Error

Sometimes reading the answer choices will make the error in the original sentence more apparent. Also, if an answer choice is more concise than the underlined portion of the original sentence and grammatically correct, then that will be the right answer.


#4: Plug the Phrase in the Answer Choice Back Into the Original Sentence

If an answer choice looks like it could be right, plug the phrase back into the original sentence. Sometimes reading the whole sentence will allow you to more easily determine if an answer choice is correct or if it creates an additional error. Use this step to verify your selection or test an answer choice you're unsure about.


#5: Go Through The Answer Choices Until You Locate the Correct Improvement or Determine that No Change is Needed

Your work is done once you find the answer choice that fixes the error in the original sentence and does not create an additonal error. You can quickly look at the remaining choices to verify that you have selected the best answer. If, after looking through the answer choices, you determine that the original sentence is correct, then select answer choice A, which is always the same as the underlined portion of the original sentence. Keep in mind that answer choice A will be right about 10%-20% of the time.


Now that we have a general approach for sentence improvement questions, we can look at the specific grammar errors that repeatedly appear in the sentences in this subsection. I'll let you know the clues for spotting these errors and how to improve sentences that contain them.


body_read_rules.jpgRead below for all the grammar rules you need to know for improving sentences.


The Specific Grammar Errors: Signs and Improvements

I arranged these grammatical errors by how often they tend to appear in sentence improvement questions, with the more common errors first and the least common ones last. All of these errors have appeared on previous SATs, and you should be familiar with all of these rules.



If a sentence suffers from wordiness, it is not written in the most concise grammatically correct way. Here are some tips for how to locate a wordy sentence.



Wordy sentences often contain gerunds in the underlined portion. Also, these sentences tend to employ the commonly used wordy phrases referenced in the article on wordiness. Once you spot a wordy sentence, it can generally be corrected in the following ways.



Remember that the most concise grammatically correct answer choice will be right. Refer to the article on wordiness for the typical corrections to the commonly used wordy phrases.



Parallelism refers to the grammar rule that requires you to use the same pattern of words for two or more words or ideas in a sentence. Errors in parallelism occur when items in a list or phrases before and after a conjunction are not written in the same grammatical form. Check out the clues for identifying a parallel structure question.



A sentence is likely testing your knowledge of parallelism if the underlined portion is part of an "x, y, and z" list construction. Additionally, if an underlined phrase follows a conjunction, it often includes a parallel structure error.

Because they're more difficult, parallelism questions tend to be found near the end of the subsection.



To correct parallelism errors, put items in a list or phrases before and after a conjunction in the same grammatical form. For example, if two items in a list are in the gerund form, then the third item should be in the gerund form as well.


Faulty Modifiers

Another common grammar error on the improving sentences subsection is the faulty modifier. The basic rule regarding modifiers is that they must be placed next to the word they're modifying. So, how do you spot a faulty modifier?



Almost all of the faulty modifier questions deal with dangling modifiers. When a sentence begins with a modifying phrase, the intro must be immediately followed by a comma and then the noun it's describing. If the underlined phrase follows an introductory clause and a comma, make sure that the noun being described comes right after the comma.



Place modifiers next to the words they describe. For the common dangling modifier questions, the noun being described should be placed right after the comma.


Pronoun Agreement

On the SAT, pronoun agreement means that pronouns must always have a clear antecedent and agree with the nouns they replace.



If a pronoun is part of the underlined phrase, look for errors in pronoun agreement. You must be able to identify an antecedent and the pronoun must agree with its antecedent in number.



Every pronoun on the SAT should have a clear antecedent. The antecedent is the noun that the pronoun refers to. If a pronoun doesn't have a clear antecedent, replace it with a noun or make sure that the improved sentence does give it a clear antecedent.

Also, make sure to use singular nouns with singular antecedents and plural pronouns with plural antecedents.


body_me.jpgMy favorite pronoun


Idioms/Wrong Word

For questions related to idioms or word choice, you have to know how to properly construct idiomatic expressions and how to properly use specific words. These questions often do not correspond with a grammar rule and are the only ones where you may have to rely on what sounds right to correctly answer the question.



The idioms on the SAT tend to involve prepositions, gerunds, and infinitives. If any of these parts of speech are underlined, make sure that any idiomatic expression in the phrase is properly constructed. If one word of a word pair is in the underlined phrase, that can also signal a wrong word error.Common word pairs include "not only...but also", "both...and", "either..or", and "neither...nor".

Note that conjunctions or adverbs in the underlined phrase can signal a word choice error as well.



Typically, an improperly constructed idiomatic expression can be fixed by changing the preposition or the verb form. Word pair errors can be corrected by replacing the word that doesn't belong in the word pair with the word that does. For example, change "either...and" to "either...or."

Make sure that the words in the underlined phrase express the intended meaning of the sentence. If the sentence shows contrast, then there should be a word like "but", "despite", or "although" in the sentence that indicates contrast.



A run-on sentence consists of two or more complete thoughts that are not separated by the proper punctuation.



Usually, you'll find a run-on sentence created by a comma splice. Two complete thoughts will be separated by a comma.



You can fix the comma splice by changing the comma to a semicolon. Or, you can change the construction of the sentence so that the comma is no longer separating two complete thoughts.



A sentence fragment doesn't express a complete thought.



Sentence fragments often have a gerund or relative pronoun in the underlined phrase. Occasionally, a participle will be in the underlined portion and the sentence won't have a verb.



Get rid of the relative pronoun or replace gerunds and participles with verbs. Make sure the improved sentence has a verb and expresses a complete thought.


Subject-Verb Agreement

Subject-verb agreement is a rule that states that all subjects must agree with their verbs in number. Singular subjects take singular verbs. Plural subjects take plural verbs.



If a verb is underlined, especially if the answer choices have different present/present perfect tense conjugations, then you should check for a subject-verb agreement error.



Change the verb from plural to singular or from singular to plural.


body_guidance-2.jpgJust a few more rules to go


Verb Forms

Verb form questions will test you on verb tenses, gerunds, and infinitives. You need to know which tense and verb form to use in a given sentence.



Verb form questions will have a verb, gerund, or infinitive in the underlined phrase. The answer choices will have different different verb forms.



Follow consistency rules with verbs and make sure that all verb tenses are being used properly. In sentences with gerunds or infinitives, verify that all idiomatic expressions are constructed correctly.


Relative Pronouns

Relative pronouns are "who", "whom", "whose", "which", "where", "when", and "that". Relative pronouns must agree with the nouns they're replacing. For example, use "where" when referring to places and "when" when referring to a specific time.



If a relative pronoun is part of the underlined phrase, then there may be a relative pronoun error.


Make sure you use the proper relative pronoun for the noun that is being replaced and that the pronoun has a clear antecedent. Occasionally, you will have to remove a relative pronoun to fix a sentence fragment.


Illogical Comparisons

The rule for illogical comparisons is that you can only compare equivalent things.



The underlined phrase will often follow a word in the comparative form. In every illogical comparison question, there will be a comparison in the sentence.



Make sure the sentence is comparing like things. For example, you have to compare books to books and people to people. You can't compare a book to a person.


Noun Agreement

Noun agreement means that a singular person/thing can't be a plural noun and vice versa. Incorrect: John and Sarah want to become a doctor. Correct: John and Sarah want to become doctors.



Multiple nouns in a sentence, including one in the underlined phrase, can signal a noun agreement error.



When necessary, make sure nouns agree in number.


Now that we're familiar with all of the specific grammar rules covered on the improving sentences subsection, here are some more general rules to keep in mind.




General Tips


The Most Concise Answer is Often Right

Underlined phrases in sentence improvement questions will often be awkward and wordy. Focus on selecting the clearest, most concise answer choice.


Consistency is Key

Many of the grammar errors have to do with inconsistency. Errors in parallelism, verb forms, and comparisons can often be fixed by focusing on consistency.


Gerunds, Especially "Being", Often Signal an Error

Sentence improvement questions tend to use gerunds to create fragments, wordiness, and idiom errors. If a gerund is part of an underlined phrase, make sure the gerund is being used correctly.

Use these tips to answer actual questions from the SAT Writing section.


Real SAT Examples

We're going to use the grammar rules and strategies you've just learned to answer the following sentence improvement question.


First, let's try to identify any errors in the underlined portion of the sentence. The presence of the gerunds "tempting" and "straining" signals that there is likely a parallelism, fragment, or wordiness error. After reading the entire sentence, you should recognize that it lacks a main verb and is not expressing a complete thought. As such, this sentence is a fragment.

One possible way to correct this error would be to change the gerunds to verbs, so let's keep that in the back of our minds as we go through the answer choices.

Immediately, we can get rid of A and D because they keep "tempting" in the gerund form, and thus don't fix the error.

Answer choice B fixes the fragment by changing "tempting" to "tempt" but creates a word choice error. The correct word pair is "not only...but also" rather than "not only...but then."

Upon first glance, answer choice C might look correct, but you should always make sure that every verb is in the proper form and tense. The subject of the sentence is "demands", which is plural. Therefore, the verb should be in the plural form. The verbs "tempts" and "strains" are in the singular form, so answer choice C creates an error in subect-verb agreement.

We're left with answer choice E. The verbs "tempt" and "strain" are consistent and they agree with the subject. The resulting sentence is no longer a fragment and there is no additional error. The correct answer is E.

We'll use the same process to answer another real SAT question from the improving sentences subsection.


Again, we'll start by trying to find the error in the underlined portion. The first word "was" is a verb. Remember to make sure all underlined verbs are in the correct form and agree with their subjects. The subject of this sentence is "two", which is plural, but the verb is "was", which is in the singular form. There is an error in subject-verb agreement.

After looking at the answer choices, we can get rid of A, B, and C right away since none of those choices correct the subject-verb agreement error.

Those eliminations leave just choices D and E, both of which replace "was" with the correctly conjugated verb, "were." However, D also includes the exra word "the," so it is less clear and concise than E.

Remember that the most concise grammatically correct answer choice will be correct. The answer is E.




What's Next?

Read this article to learn the big secret to SAT Writing.

If you want more review on all of the grammar rules tested on the SAT Writing section, check out the complete guide to SAT Writing grammar and what's actually tested on SAT Writing.


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Justin Berkman
About the Author

Justin has extensive experience teaching SAT prep and guiding high school students through the college admissions and selection process. He is firmly committed to improving equity in education and helping students to reach their educational goals. Justin received an athletic scholarship for gymnastics at Stanford University and graduated with a BA in American Studies.

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