Some 'mistakes' may be both acceptable, proper


“It must drive you nuts to see all the mistakes bad writers make!”

When people learn your job is to catch writing errors, many guess that you’re so laser-focused on seeking out grammar, punctuation and spelling slip-ups that it’s nearly impossible to focus on the meaning of anything you’re reading.

They’re half right.

Yes, I’m driven nuts by minutiae of others’ writing. But no, it’s not bad writers’ work and, in fact, it’s not even their mistakes.

Fixing errors is only part of my job as a copy editor. Another part, a big part, is fixing things that aren’t errors. Case in point: this passage from the novel “The First Fifteen Lives of Harry August”: “I found that Thai was the only language which wanted to pass my lips in any coherent form, and the only word which I seemed capable of forming was, why?”

What’s wrong with that, you might ask? Nothing. Nothing at all. Yet a word in this sentence distracted me from the story in this excellent book. That word, which was used twice in this sentence, is “which.”

According to every rule of grammar, “which” is just fine in this sentence. But according to the two leading style guides for American editors, these whiches are errors. If I had edited the passage, I’d have been compelled to change them both to “that”: the only language that wanted to pass my lips; the only word that I seemed capable of forming.

That’s because AP and Chicago editing styles say you have to use “that,” not “which,” for restrictive clauses.

What’s a restrictive clause, you ask? It’s a clause that narrows down a noun. It can’t be lifted out of the sentence without harming the meaning or specificity of the main clause. It’s the opposite of a nonrestrictive clause, which can be chopped right out of the sentence while leaving the noun just as specific and the main clause just as logical and sound.

Take the sentence: “Brad’s car, which I had borrowed, ran out of gas.” What’s the main clause, the main message of the sentence? It’s “Brad’s car ran out of gas.” The part about how I borrowed Brad’s car isn’t crucial to the main clause. It’s extra information. An add-on. Chop it out and the idea that Brad’s car ran out of gas isn’t harmed at all. So the car-borrowing business doesn’t narrow down or restrict Brad’s car in any way. “Which I had borrowed” is, therefore, a nonrestrictive clause.

Now take the sentence: “The car that I had borrowed ran out of gas.” Remove all that car-borrowing business from this sentence and you have an entirely different situation: “The car ran out of gas.” What car? Unless the reader has more context, she has no idea what car you’re talking about. The clause “that I had borrowed” narrows down which car we mean by “the” car. It restricts the noun “car.” Makes it more specific by limiting its possible scope of meaning. So in this sentence, “that I had borrowed” is a restrictive clause.

Notice, too, how the commas come into play. Commas often set off nonessential, parenthetical information: My friend, an accountant, ordered the rigatoni. That’s why “which” clauses are set off with commas and “that” clauses aren’t.

Bonus points if you noticed that I mentioned this all has to do with American editing styles. British English doesn’t fuss with this matter the way American publishers do. In fact, Brits are far more inclined to use “which” for restrictive clauses.

“The First Fifteen Lives of Harry August” is a British book published by a U.K.-raised author. So the passage isn’t just acceptable. It’s proper.

– June Casagrande is the author of “The Best Punctuation Book, Period.” She can be reached at


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