When to Form a Plural with an Apostrophe
This reader wants to know why we write 1980s and not 1980’s.
I understood that making text entities with non-letter characters into a plural form, you separate the s from the term with an apostrophe – 1900’s, Jones’, Smith’s, or Bang!’s. So, why no apostrophe with 1980s?
A lot of writers share this reader’s understanding that non-letter characters are pluralized by adding apostrophe s.
Alas.
Alas, indeed. That pesky apostrophe raises a lot of blood pressure for writers of English.
If I had my druthers, we’d phase out altogether the use the apostrophe to form the possessive of nouns. What meaning would be lost if we wrote my mothers birthday, the cats tail or the cats tails?
Teachers and editors could save their red ink for dealing with the apostrophe and plurals.
NOTE: I’ve received so many protests regarding these facetious remarks that I hereby withdraw them. We do need the apostrophe to form the possessive. Mea culpa, dear readers.
I can’t really answer the reader’s question. What I can do is lay out what the Chicago Manual of Style says about when to use an apostrophe and when not to. And it has a lot to say. Here are only some of the rules this style guide offers.
Don’t use an apostrophe to pluralize a proper name or other capitalized noun:
Many Pakistanis have immigrated to the U.S. (not Pakistani’s)
I’ll be occupied for the next three Thursdays. (not Thursday’s)
The Jeffersons live here. (not the Jefferson’s)
NOTE: The CMS suggests that if you want to pluralize an awkward name like Waters or Rogers, you may want to reword the sentence to avoid writing the Waterses or Rogerses. (or Maddoxes?)
Don’t use an apostrophe to pluralize a title:
I have three Madame Bovarys and five Animal Farms. (Type the title in italics and the s in Roman face.
When forming the plural of words and hyphenated phrases that aren’t nouns but are used as nouns sometimes you do and sometimes you don’t:
I want no ifs or buts.
Here are the dos and don’ts of blogging.
I’ve written 25 thank-yous.
BUT
I’m tired of all his maybe’s.
DO NOT use an apostrophe to form the plural of capital letters used as words, abbreviations that contain no interior periods, and numerals used as nouns:
the three Rs.
the 1990s
lengthy URLs
NOTE: For the abbreviations p. (page), n. (note), and MS (manuscript), the plurals are pp., nn., and MSS
And for you scientific types, special rules apply for the plural of SI symbols:
No periods are used after any of the SI symbols for units, and the same symbols are used for both the singular and the plural. Most symbols are lowercased; exceptions are those that stand for units derived from proper names (A for ampere, etc.) and those that must be distinguished from similar lowercased forms. All units are lowercased in their spelled-out form except for degree Celsius (°C).
For those of you who, like me, hadn’t heard of SI symbols, you’ll find a list here.
DO use the apostrophe to form the plural of an abbreviation that combines upper and lowercase letters or has interior periods:
The department graduated five M.A.’s and two Ph.D.’s this year.
NOTE: If you leave out the periods, you can write MAs but you’d still have to write PhD’s.
DO use the apostrophe to form the plural of lowercase letters:
Mind your p’s and q’s.
DO NOT use the apostrophe to form the plural of capital letters:
What the CMS actually says is
Capital letters do not normally require an apostrophe in the plural.
One could write a sentence like this without confusing a reader:
You need to improve the formation of your Ts and Zs.
But one might be tempted to reach for the apostrophes with a sentence like this:
You need to improve the formation of your Ss, Is, and Us.
And finally—DRUM ROLL–our reader’s question about using an apostrophe with non-letter characters:
DO NOT use an apostrophe to form the plural of a number:
The 1920s were noted for excess.
I bowled two 300s and two 238s.
Source: Chicago Manual of Style, paragraphs 7.9, 7.12, 7,14, 7.15, 7.16, 7.65, 9.59.
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Thanks. I think part of my confusion, was confusing the plural of the 1980s with the possessive – such as 1980’s music. Or would it be 1980s’ music, if I meant the whole decade?
Great post. I’ll add a piece from our post on this topic.
Sentences like “Get your hamburger’s here” are simply wrong. The little apostrophe was not meant to make one hamburger into multiple hamburgers. Here are a few other samples of the apostrophe being pressed into the wrong service:
“These paper’s need correcting.”
“Two boy’s were bragging about their dog’s.”
“Apostrophe’s are complicated.”
Why do people do this to the apostrophe? The construction ’s is meant to show ownership or a contraction, not a plural. Perhaps people abuse the apostrophe in this way because they don’t know the difference between ownership and plurals. Perhaps they see this abuse occurring so often that they don’t even realize it is wrong (much like using “data” as a singular noun although it is really a plural.)
Villainous sentences like “People living in the 1990’s bought a lot of CD’s” certainly don’t promote virtuous use of the noble apostrophe.
The rest of the article:
http://preciseedit.wordpress.c.....phe-abuse/
Thanks, Maeve, for keeping this topic alive! Perhaps we can stem the tide of apostrophes used to make plurals.
All of your examples are unambiguous, but it is easy to come up with an ambiguous example: Does “the boys books” refer to the boy’s books or the boys’ books?
Surely it’s better to retain those aspects of the language which help to resolve ambiguity.
Daran,
I concede.
This is a great resource.
However I’m not sure I agree that possessive apostrophes should be removed from English writing. It would be too bizarre.
My biggest question has to do with names that end in s. The Adams’ house? The Adams’s house? Happy holidays from the Adams? Yikes.
The New York Times is one of the biggest sinners when it comes to wrongfully using years with apostrophes – kills me every time
To Leslie (commenter #6, above):
I believe Meave covered that subject in an early part of this post. I don’t think “Adamses” is all that awkward, but can see the opposite view as valid. What gripes me (surely the subject of a different post) is the misuse of the apostrophe to form the possessive without the extra ’s’: “Charles’ pen” needs correction to “Charles’s pen.”
As a writer, I find that you can generally get by with a few easy rules:
1) Use an apostrophe to indicate possession (e.g., Sharon’s, the boys’, etc.).
2) Use an apostrophe to indicate a contraction (e.g., can’t, doesn’t).
3) Use apostrophes to indicate a quote within a quote (e.g., Simon said, “Billy said, ‘No way!’”).
The exceptions are just needlessly confusing and may be ignored unless confronted by a strict grammarian. If that is the case, blame the error as being a “typo”, and beg forgiveness.
The SI symbols simply represent metric units (metres, litres, degrees Celsius, Kelvin, etc.) The site you linked to listed the metric prefixes. The prefixes are only used in conjunction with metric units. For example, the prefix ‘kilo-’ is combined with the unit ‘metre’ to denote the ‘kilometre’ unit. The prefix ‘kilo-’ multiplies the value of the unit it is attached to by 1000 (a kilometre is 1000 metres).
Also, Kelvin, the SI unit of temperature, is written with a capital letter in its spelled-out form.
I suspect, like the metric system, the imperial system would follow the same general rules. It would be unlikely to see, “There are 1000 lb.’s in 1 ton.”
One issue that I seldom see documented, if ever, anywhere, is the recommended usages of abbreviations for days of the week. In a publication listing events, space is often limited and usage of days of the week must be reduced – i.e., Saturday becomes Sat.
In addition to abbreviated day name usages – Thu. or Thurs. – comes another common problem for me, which is abbreviating plural days of the week, for events held weekly – Saturdays at 8 p.m. How would this be abbreviated for space? Sats. at 8 p.m.? Sat.’s at 8 p.m.?
I would love to hear solutions from other anal-retentive copy editors…
The SI symbols simply represent metric units (metres, litres,
A particular set of metric units (there are other metric systems that are not SI)
degrees Celsius, Kelvin, etc.) The site you linked to listed the metric prefixes. The prefixes are only used in conjunction with metric units. For example, the prefix ‘kilo-’ is combined with the unit ‘metre’ to denote the ‘kilometre’ unit. The prefix ‘kilo-’ multiplies the value of the unit it is attached to by 1000 (a kilometre is 1000 metres).
Except the base SI unit of mass is the kilogram, not the gram
Also, Kelvin, the SI unit of temperature, is written with a capital letter in its spelled-out form.
You’re a bit out of date—it used to be “degree Kelvin” before 1967; now it’s just “kelvin”: no capitals.
Peter, one side note about prefixes.
In computers, kilo-, mega-, giga-, and tera-, and peta- have binary definitions, instead of the 10 ** 3 (1,000, or one thousand) definition used in SI and other metric systems.
The binary definition of kilo, is 2 ** 10, or 1,024.
2 ** 20 (1024 x 1024) would be like for megabytes, or 1024 kilobytes.
2 ** 30 would be for gigabytes, or 1048576 kilo bytes.
2 ** 40 would be 1,045,576 megabytes, or 1 terabyte, same as 1,024 gigabytes.
2 ** 50 would be peta, or 1,024 terabytes. Or 1,024 x 1,024 x 1,024 x 1,024 x 1,024 bytes.
Remember when you wanted the PC/XT, with 128 k RAM instead of the basic 64k (64 kilobytes)?
I just thought I would mention this. When the world (outside of computer types) think “kilo” or “k” means 1,000 – there is this nagging worry about a hard drive with 256 gigabytes of storage (1,024 / 4 = 256, another “even” binary number). No, they didn’t round off the numbers badly.
Yes; except that disk drive manufacturers use the standard multiple of 1000, except for kB, so 1 GB of disk space is actually 1,024,000,000 bytes, but 1 GB of memory is 1,073,741,824 bytes, just to confuse people!
Officially, there are binary prefixes: “Ki”, “Mi”, “Gi”, etc. (pronounced kibi-, mebi-, and gibi-); you’re supposed to use “KiB” to mean 1024 bytes, and “kB” to mean 1000 bytes, and so on—but I don’t know anybody who does.
{Actually, the use of “byte” to mean “8 bits” is in a similar situation; “byte” properly just means whatever unit the processor uses—there have been computers with anything from 6 to 72-bit bytes, that I know of; technical standards often use “octet” to avoid ambiguity}
Peter,
There have always been a few errant marketing uses for “byte”, but the accepted meaning has been 8 bits.
The unit that the processor uses, from 1 bit to 128 bit or larger, was called “word”. MS Windows is available for 32 bit and 64 bit word size processors. The old US Navy “Bravo” computers used a 22-bit word size, and all magnetic core memory, and could play “Jingle Bells” on your FM radio.
As late as the mid 1980s, in some cases, the standard use of “byte” didn’t mean 8 bits (except in IBM, where the “8 bit” definition originates). MS Windows (really, IBM x86 compatible processors) uses a 32 or 64 bit word size, but the addressing unit is still 8 bits; but older computers often had an addressing unit of different width (the last one I know of to use a non-8-bit “byte” size was the last generation of Lisp Machine hardware, the Symbolics Ivory processor, using 48-bit bytes).
What is the plural form of the grades A-, A+, B+, etc.?
As an irritatingly pedantic professional writer, it is a great relief to find a website where I can vent my frustrations.
I know I’m coming late to this conversation, but I really wanted to add that I recently had the same thought myself: it’s hopeless trying to save the apostrophe from its ubiquitous/iniquitous abuse. Better to simply abolish it.
The difference between ‘the boys books’ and ‘the boys books’ would be obvious from the context, and if it weren’t, a small effort would make it obvious. The apostrophe today is like a hangnail – we only notice it when it snags on something and then it hurts like hell.
How seemingly simple, to eradicate apostrophe abuses by abolishing it! What is so difficult about understanding possessions and contractions? What is so difficult about understanding singular and pleural?
I am grammatically challenged but,
its -possessive
it’s – it is
contradicts the possessive rules, no?