Sometimes we want a comma before the subordinate conjunction because, and at other times, we don’t. If we’re not careful, the presence or absence of a comma can result in a meaning different from what we intended.
Can you see the difference in these examples?
- You shouldn’t buy that car because it’s not the right color.
- You shouldn’t buy that car, because it’s not the right color.
Without the comma, the advice is to not use color as the criteria for choosing which car to buy. With the comma, the advice is to use color as the criteria, the opposite in meaning.
Consider these examples:
- He didn’t go to the game because he didn’t have a ticket. (He had a ticket but missed the game because he was sick.)
- He didn’t go to the game, because he didn’t have a ticket. (The game was sold out, so he couldn’t go.)
Without the comma, we understand that his not having a ticket was not the reason he missed the game. He had a ticket but couldn’t go because of a conflict. With the comma, we know would have gone if he had a ticket.
When the subordinate clause is essential to the main thought of the sentence, we don’t want a comma before the conjunction.
- Perhaps at times, the reason we have been reluctant to share our stories is simply because we haven’t recognized how important they are to others.
- He decided to stay home because of the icy roads.
In the following examples, the meaning doesn’t change much, with or without the comma.
- You should go to the party because you’ll meet new friends there.
- I gritted my teeth because I was angry.
With the comma, the main thought is stronger, and the subordinate clause is more explanatory in nature.
I am more confused than ever.
You’re not alone. Bestselling authors and great editors don’t always catch the distinction, which is why I felt it necessary to give so many examples. Sometimes I’m helped by reading the information more than once. That way, something unfamiliar has time to soak in and become more familiar.
The determining factor hinges on whether a phrase restricts or explains the main statement of the sentence. Sometimes it helps to leave out the “because” phrase. If the meaning of the remainder sentence changes, then the clause is restrictive and there should be no comma before “because.” But if the “because” statement merely adds useful information, then we have an explanatory clause and should have a comma.
When the presence or absence of the comma changes the meaning to the opposite of what we intended, readers may still get the correct idea from the context. But it’s a risk we shouldn’t take if we can avoid it.