Although my instinct is to proffer profuse apologies for my four-week silence, I have, by now, divested myself of any illusions that my writing is of particular importance to anybody but me. Thus, chances are that nobody has missed my musings – but if you have, both a hallelujah and an apology are in order. We are having a most glorious September, and I have been roaming our fabulous mountains more or less non-stop since my last post. Today’s murky interlude has given me the opportunity to tackle one of the killer commas infesting writing as far as the eye can see. It goes like this.

“Where’s Doug?”

“No longer with us, I’m afraid.”

“Oh dear, how awful!”

“Indeed.”

“When did it happen?”

“Nearly a month ago.”

“Did you attend?”

“Attend what?”

“The funeral, of course.”

“Whose funeral?”

“Doug’s – of course.”

“What do you mean Doug’s: Doug’s alive and kicking.”

“But you said …”

“No, no, no, no: Doug’s got the sack.”

“O-o-o-o, thank goodness. I mean, it’s awful, but …”

“No worries: I know what you mean.”

“Why did they sack him?”

“Over a comma.”

“You mean he was in a coma and they kicked him out?”

“No, no, no, not a coma – a comma.”

“What comma?”

“The one with which he threatened the entire teaching profession. That’s what he wrote.”

We will apply severe sanctions against all teachers, who tolerate disruptive behaviour.

“Oh dear!”

“Indeed, indeed. The SMUT had a field day with this one.”

“I can imagine; our esteemed Sagacious and Meritorious Union of Teachers has been known to kick up a stink over lesser stuff than this.”

“Indeed. Doug had already been on a warning, so they had no option but to show him the door.”

“What was the warning for?”

“Another idiotic comma. That’s what he’d e-mailed to all schools.”

We are going to come down hard on teachers, who are incompetent.

“Jeepers! But he’s in good company. I mean, look how many people can’t tell defining relative clauses from their non-defining counterparts.”

***

And so they can’t. Relative clauses begin with relative pronouns who, which, whose, whom and that and offer additional information about somebody or something. There are two types of relative clause: defining (or restrictive) and non-defining (or non-restrictive). Because defining relative clauses (such as those in Doug’s missives to teachers) give essential information, they must never be separated from the rest of their sentence by a comma – or commas. What the hapless Doug should thus have written was this.

We will apply severe sanctions against all teachers who tolerate disruptive behaviour.

We are going to come down hard on teachers who are incompetent.

By contrast, non-defining relative clauses supply merely additional details, which is why the sentence of which they are a part usually makes perfect sense without them. And if a section of a sentence can be removed without this operation affecting meaning, such a section always gets separated with either one comma or two (depending on its position in a sentence). Below are given three sentences containing non-defining relative clauses: even if you remove each of these clauses (italicised), the rest of the sentence can stand on its own quite happily.

I was born in Poland, which has beautiful mountains.

I am extremely fond of Pat, who is my friend.

My neighbour, whom I haven’t seen for a while, has suddenly reappeared.

Interestingly, this simple principle appears to have escaped a great many writers – although not many great writers. Here are a few examples.

Incorrect

A growing number of people, who used to live in the city before retiring, are moving back to London. (The Sunday Times)

Correct

A growing number of people who used to live in the city before retiring are moving back to London.

Incorrect

A few years ago there was a scene, in which the class moved from quiet to riot inside three minutes. (The Times Educational Supplement)

Correct

A few years ago, there was a scene in which the class moved from quiet to riot inside three minutes.

 Incorrect

We need to encourage structures, which engage students actively in defining their goals. (The Times Educational Supplement)

Correct

We need to encourage structures which engage students actively in defining their goals.

Incorrect

Young people aged 14 and 15, who care about equality and want to build a fairer society, are being sought by the Equality and Human Rights Commission. (The Times Educational Supplement)

 Correct

Young people aged 14 and 15 who care about equality and want to build a fairer society are being sought by the Equality and Human Rights Commission.

 Incorrect

Imagine you are a happily married man of 29, whose only problem is that your wife is failing to conceive. (The Sunday Times)

 Correct

Imagine you are a happily married man of 29 whose only problem is that your wife is failing to conceive.

But these examples are merely a drop in the ocean foaming with this illiterate comma. Equally common is the absence of a comma, or commas, demanded by non-defining relative clauses – but that’s the subject for another article.