Apostrophes
Most writers know that an apostrophe shows possession for a noun; the omission of some letters in a word or numbers in a year; and the plurality of single letters, numbers, and abbreviations. But the apostrophe has other uses as well that may not be in the forefront of our minds when we are writing. Refresh your knowledge of the apostrophe by reviewing its other uses below.
Double possessive (double genitive): using of and apostrophe s in the same phrase
a friend of Mary’s
a brother of mine
Joint possessive: using an apostrophe on the last item in a series when the subjects own an item together
Frank and Sue’s house (they share one house)
Frank’s and Sue’s houses (they each have a house)
Bob, Tim, and Fred’s sister-in-law (they have the same sister-in-law)
Possessives of possessive names: do not use another apostrophe s if the name of a company or thing is already possessive; recast the sentence of use the original possessive name again
Mary and Mariah love going to Friendly’s. Friendly’s fries are the best, they say.
Mary and Mariah love going to Friendly’s. The fries at Friendly’s are the best, they say.
Possessives of inanimate objects:
The car’s engine is overheating.
The laptop’s hard drive is broken.
Set phrases: use apostrophe s in an idiomatic way for a couple of set phrases
mother-in-law’s car, not mother’s-in-law car
anyone else’s book, not anyone’s else book
Units of measurement: use an apostrophe when the unit modifies a noun
15 years’ experiemce
two weeks’ notice
4 yards’ worth of fabric
The omission apostrophe: use an apostrophe when making contractions
don’t
wouldn’t
po’ boy
The plurals apostrophe: use an apostrophe when making single letters, numbers, and abbreviations plural
Robert got all A’s on his report card.
Disco was popular in the 1970’s.
The CEO’s are meeting after the VP’s.
Note that whether or not an apostrophe is used to form plurals depends on the style guide you are following. The above examples follow the rules of the New York Times. For example, the Chicago Manual of Style, 16th edition, recommends the following:
Robert got all As on his report card.
Disco was popular in the 1970s.
The CEO’s are meeting after the VPs.
Try It!
Determine which word in italics is correct.
1. A friend of Beth’s/Beth came with us to the movies.
2. John and Sally’s/John’s and Sally’s house has three bedrooms.
3. Susan and John like T.G.I. Friday’s’s fries. / Susan and John like the fries at T.G.I. Friday’s.
4. The book/book’s pages are crumpled.
5. My brother’s-in-law/brother-in-law’s truck is red.
6. I decided to give my two weeks notice/two weeks’ notice today.
7. I wont/won’t go to bed until I brush my teeth.
8. Rebecca got all B’s/Bs in her English class.
9. The Beatles were very popular in the 1960s/1960’s.
10. The VPs/VP’s are meeting after lunch.
Answers:
1. Beth’s; 2. John and Sally’s; 3. T.G.I. Friday’s; 4. book’s; 5. brother-in-law’s; 6. two weeks’ notice; 7. won’t; 8. B’s; 9. 1960’s; 10. VP’s
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Martha Hart
9/26/2011
What a lovely site.. incredibly useful information and well-presented to boot on services/pricing (managing the prospective client’s expectations) … and I love apostrophes, so couldn’t resist taking a look here. Nice coverage of some uses people don’t immediately think of… and thanks for pointing out differences in style guides. Most people who write about grammar do so from their preferred style…. me, I’m a CMOS person, so your ## 8, 9 and 10 look odd to me, but it depends (often, on your audience).
Anyway… nice, and I’ll check in on the blog from time to time.
Cheers,
Martha
…oh, you might consider changing “of” to “or” in the possessive of possessive names part: “… recast the sentence of use the original” (so hard to read our own stuff!)