Q From Michael Wilson: I was watching Never Mind The Full Stops on BBC4 recently, in which an altercation broke out between Julian Fellowes and one of the panellists over spelling. Was it mind your ps and qs or mind your p’s and q’s? When the programme ended I logged on to World Wide Words for your views. It was as usual very interesting. But as a struggling apostrophe user I was puzzled when you wrote mind your please’s and thank-you’s. Are you not simply talking about the plural of please and thank-you, which surely require no apostrophes? What have I missed?
A Your puzzlement is understandable. Everybody gets confused these days about when to use the apostrophe, never more so than in this situation. It doesn’t help that style guides differ somewhat in their advice, that the rules are changing, and that, as so often, US usage is more conservative than in some other countries.
The older rule was that apostrophes formed the plurals of letters of the alphabet (you have too few s’s in Mississippi), of abbreviations and numerals (none of the MP’s voted for the measure; he was stoned for most of the 1960’s), and in those situations in which the word was being referred to as a word rather than being used normally (if if’s and an’s were pots and pans!).
Nowadays, it’s normal to omit the apostrophe when we make plurals of abbreviations and numerals (both the CPUs overheated; married by their early 20s). That the superfluous marks are often recycled to make plurals (lettuce’s and cucumber’s) is just one of those little ironies of usage.
But opinions differ on what to do with words being referred to as words without regard to their usual meaning. Take the phrase do’s and don’ts. Some style guides — such as the Oxford Style Guide — suggest writing it as dos and don’ts and that’s how it usually turns up in British sources. But it also often appears with the apostrophes — this is the advice in some books (we may ignore Lynne Truss’s suggestion in Eats, Shoots & Leaves that it should be do’s and don’t’s; it’s logical, but it’s also awfully ugly). There’s less argument over words that have become part of fixed phrases (whys and wherefores, oohs and ahs, ins and outs) with the consensus being that apostrophes are otiose here. It’s also still standard for single letters of the alphabet to be made into plurals with apostrophes; Dr Burchfield’s advice in the third edition of Fowler’s Modern English Usage is to retain them in situations in which leaving them out might lead to confusion (dot your i’s and cross your t’s; there are three i’s in “inimical”; mind your p’s and q’s).
This leaves the situation you query. Should the phrase be written as mind your please’s and thank-you’s or mind your pleases and thank-yous? The advice is inconsistent, though the style guides mostly say the version with apostrophes is better. The piece you’re quoting was written a decade ago and my gut feeling is that these days I’d prefer to leave the apostrophes out, such is the speed of change (I’d now rewrite another of Lynne Truss’s examples without the fly specks as Are there too many ands and buts at the beginnings of sentences these days?).
The apostrophe still also appears in phrases like he sent brief thank-you’s to his teammates, though by a clear margin more often in US usage than British. That case is much more clear-cut, since thank-you is an elliptical form — which has been known since the end of the eighteenth century — for a letter or other expression of thanks (did you send her a thank-you?), not a word that’s being commented on, so it’s an ordinary noun that should take a standard plural (Hannah Poole wrote in the Guardian in November 2006: I leave a trail of hellos and goodbyes and thank-yous wherever I go). Americans may remain unconvinced that this is quite the done thing, despite thank-yous having a long history in that country (I’ve found it as far back as the 1860s).
The shift is towards leaving out the punctuation and letting the context determine whether — for example — you mean the verb is or the letter plural i’s. However, it will be a while yet before it becomes accepted by everyone.