So after months of living under a rock in a desperate attempt to finish my revised SAT books in time for the summer stampede, I’m finally taking a few tentative steps into the sunlight.

Several of you have written to me lamenting my lack of acerbic commentary on the June SAT scoring scandal, the new SAT, and other educational embarrassments, and I promise you that I am well aware of that shortcoming. Rest assured that I do in fact have many, many things to say; I’ve merely had to devote every last brain cell to rewriting my books for the last half-year, leaving me precious little room for other thoughts, acerbic or otherwise. I’m hoping to begin posting some commentary here in the next weeks.

For the moment, though, I want to address a topic that a couple of people have written to me about recently, namely the “no comma before ‘because’ or ‘since’ rule.”

Actually, it’s not really a “rule” per se. It’s more of a guideline. In the universe of SAT grammar errors, it’s a pretty minor one, and for that reason it’s pretty certain that an answer’s correctness/incorrectness will never depend exclusively on it. It’s merely a secondary consideration.

Let me back up and explain.

There are two main types of conjunction: coordinating and subordinating.

Coordinating conjunctions (for, and, nor, but, or, yet, so) are also known by the acronym FANBOYS. They can be used to join two independent clauses (complete sentences) and must always follow a comma when employed in this way.

Correct: The city’s government has curtailed spending on all non-essential services, so the new theater company has been forced to suspend its productions for lack of funding.

A FANBOYS conjunction can only be used at the start of the second clause; it cannot be used at the start of the first. Even if you don’t know the grammatical rule, you should be able to recognize that this usage does not make any sense.

Incorrect: So the new theater company has been forced to suspend its productions for lack of funding, the city’s government has curtailed spending on all non-essential services.

Subordinating conjunctions on the other hand, can be used to start either the first or the second clause. Common subordinating conjunctions include because, while, since, when, until, and unless.

Now, here’s the rub. If you are being absolutely, technically correct, a comma should be used to separate two clauses when the clause begun by the subordinating conjunction comes first.

Correct: Because/Since the city’s government has curtailed spending on all non-essential services COMMA the new theater company has been forced to suspend its productions for lack of funding.

When the clause begun by the subordinating conjunction comes second, no comma should be used (although there is an exception for “strong” subordinating conjunctions such as although and even though, which do take a comma).

Incorrect: The new theater company has been forced to suspend its productions for lack of funding COMMA because/since the city’s government has curtailed spending on all non-essential services. 

Correct: The new theater company has been forced to suspend its productions for lack of funding NO COMMA because/since the city’s government has curtailed spending on all non-essential services.

That’s the strict version of the rule. The more complicated truth is that it depends on context: if a sentence is very long, or it seems necessary to insert a comma before because in order to make the meaning of the sentence clear, then that construction is acceptable.

From what I’ve observed, the College Board/ETS/whoever it is setting the rules tends to adhere to the strict version: answers that contain the construction comma + because/since are pretty much always wrong. (Please note that this pattern was observed in regards to the pre-2016 SAT only.)

That said, wrong answers with that construction almost always contain an additional problem that makes them absolutely, incontrovertibly wrong. So maybe it’s more correlation, not causation.

A while back, someone contacted me about a question in the online program that violated that rule; an answer with the construction comma + because was correct. That did make me rethink things, but only up to a point. I’ve found slight inconsistencies between the online tests and real tests in the past, and I’ve never seen a question from an administered test that broke this “rule” (although if anyone reading this post has seen one, please let me know!).

My suggestion, therefore, is to work from the standpoint that any answer with the construction comma + because/since is probably wrong, and only reevaluate that assumption if there’s a clear grammatical problem with every other answer. To be fair, the SAT does break its own “rules” sometimes, and this one isn’t particularly hard and fast. But still, you’re better off playing the odds and working from there.