Identify Preposition Errors in SAT Writing

Preposition ErrorsA Guest Post By Veritas Prep

Many students find that prepositional phrases are the bane of their existence on the writing section of the SAT.  The SAT likes to use propositional phrases to confuse test takers by adding a bunch of words in between the subject and verb or the pronoun and the antecedent.  Armed with foreknowledge, you can catch the test-writers at their game and never get fooled again.  Here’s what you need to know…

How to identify a prepositional phrase:

  • Prepositions are little words that indicate location in time and space; common examples include “at,” “in,” “through,” “before,” “above,” “without,” “along,” “beyond,” “with,” etc.
  • A prepositional phrase begins with a preposition and ends with an object (which could be a noun, pronoun, gerund, or clause), and might have modifiers in between the preposition and its object.

An important note about prepositional phrases:

  • A prepositional phrase can NEVER contain the main subject or verb of a sentence.  Because of this, prepositional phrases often serve as red herrings in SAT writing questions, masking agreement errors (or occasionally making it seem as though there is an agreement error when there isn’t one).

….So, what can you do about that?

  • Identify and bracket prepositional phrases whenever you see them in an SAT writing question.
  • With those out of the way, identify the subject and verb and/or any pronoun/antecedent pairings and check for agreement.
  • If no agreement errors are evident, then you should check the prepositional phrase for errors: in particular, if the preposition is underlined, check to be sure it’s the idiomatically correct preposition for that expression (e.g. “opposed to” vs. “opposed from, “listen to” vs. “listen at,” etc).


In the morning, the group of students, with their backpacks and No. 2 pencils in tow, are waiting patiently by the bus stop.

Let’s bracket those prepositional phrases:

[In the morning], the group [of students], [with their backpacks and No. 2 pencils in tow], are waiting patiently [by the bus stop].

Now look at the simplified sentence and check for agreement issues:

The group are waiting patiently.

“group” is singular; “are” is plural. Subject-verb agreement error spotted!


That the flood of emails was surprising for Emily explained her confusion upon trying to answer them.

Let’s bracket those prepositional phrases:

That the flood [of emails] was surprising [for Emily] explained her confusion [upon trying to answer them].

No we can simplify and check for agreement issues:

That the flood was surprising explained her confusion.

No problems there! Now let’s check those prepositional phrases for idiomatic correctness.

“of emails” is okay.

“surprising “for Emily” is not okay – that should be surprising “to Emily.”

Idiom error spotted!

Do a little research on common prepositions and idiomatic phrases involving prepositions, and then use SAT questions to practice identifying and bracketing prepositional phrases, simplifying and checking for agreement errors, and (as needed) checking for idiomatic preposition errors.  Soon enough, you will be an SAT preposition rock-star!

Bobby Touran is the founder and CEO of ApplyKit. ApplyKit helps students manage their entire college application process and also provides key resources to help them excel every step of the way.