Find out how to use “used to” and “different from” and how to make acronyms plural.
Making Acronyms Plural
Hi, Grammar Girl. This is Kay from Kirkland. If we are using the letters of an abbreviated term—for instance CPA for certified public accountant—I see different usages for two of them. I would think if you were talking about two CPAs who went to lunch it would be CPAs, but I often see it used with an apostrophe s (CPA's). I've seen different usages in The New York Times and Seattle Times. Which do you think is the best usage?
Previously, I reported that although the most common way to make an acronym or initialism plural is to add an "s" to the end, there was one notable holdout: The New York Times, which insisted on using an apostrophe to make acronyms and initialisms plural. Well, I'm thrilled to report that just a few weeks ago, The New York Times changed its style and will no longer use apostrophes to make acronyms and initialisms plural! So I now feel more confident than ever advising you to make initialisms and acronyms plural by simply adding an s to the end.
Neil asked a related question: how to make initialisms plural when you’re pluralizing the first word of the phrase when it is written out. For example, RBI can stand for run batted in or runs batted in. Well, Neil, it's OK to add an s to the end of RBI to make RBIs the plural of runs batted in, even though the s is added to run when you write the whole thing out. So a run batted in is an RBI, and runs batted in are RBIs.
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