Paying attention to sentence structure on the ACT and SAT is extremely important, errors in structure account for a large percentage of incorrect answers on both tests.

Did you spot or “hear” the error in the previous sentence? Welcome to the comma splice, an oft-encountered yet commonly overlooked sentence structure error tested on the SAT and ACT. Comma splices occur when a comma is used to join two “parts” (clauses) that can stand alone as complete sentences (independent clauses). In the incorrect sentence above, here’s what we’ve got.

Paying attention to sentence structure on the ACT and SAT is extremely important, errors in structure account for a large percentage of incorrect answers on both tests.

Both the blue and the red clauses are independent–––each can stand alone as its own sentence. To remedy the error, we’d need to replace the comma with another piece of punctuation, such as a period or semicolon. Even a long dash (–––) or a colon would be a suitable replacement in this case. A comma, however, is straight up incorrect.

This type of structural error is all over the SAT Writing & Language section and the ACT English section. Here are two examples from recent exams. (Note: these examples are from exams have been released to the general public by their respective organizations, and are not our original content).

May 2016 SAT

May SAT ex-1.jpg

June 2014 ACT

June 2015 ACT ex.jpg

Note that in both cases, we get a comma splice. For the first question, we can correct the error by choosing D, which makes the second (red) clause dependent (i.e., not a complete sentence), and thus permits a comma. In the second question, we can eliminate the comma splice by choosing choice G, which uses a colon to separate two clauses that can each stand alone (note that the other choices all use different pieces of punctuation incorrectly).

How do you spot this error on the test? For each of the questions above, look at the answer choices. Notice how all they do is change the punctuation and structure slightly. That's typically a giveaway that you're dealing with a question testing structural correctness, and serves as a tipoff that a comma splice may well be at play.