Why this matters on the SAT
An apostrophe on a noun does one job: it says the noun owns something. You'll know these questions by their choices, the same nouns with the apostrophe moved, added or dropped, and sometimes an -s added too (committee’s, committees’, committees). They make up about one in twenty-two grammar questions, and for each noun they're really asking two things: does it own the next word, and if so, how many owners are there? Committees, committee’s and committees’ all sound the same, so your ear can't help here. The two questions can.
Solution to the example
Test each noun. Committee owns the recommendations (the recommendations of the committee), so it takes an apostrophe, and the passage names one committee, so it's committee’s. Recommendations is followed by a period, so it owns nothing and takes no apostrophe. The answer is C. A tempts most, because it puts an apostrophe on both nouns, but nothing comes after recommendation’s for it to own. B makes the owner several committees, and D puts the apostrophe on the wrong noun.
SAT example
Last year, a city council formed a committee to propose changes to local zoning rules. When the committee delivered its report at a public meeting, council members scrutinized the ____ Before voting, they discussed whether the wording of each proposal was clear.
Which choice completes the text so that it conforms to the conventions of Standard English?
committee’s recommendation’s.
committees’ recommendations.
committee’s recommendations.
committees recommendations’.
On a noun, an -s with no apostrophe usually just makes it plural: one keeper, two keepers. An apostrophe adds something else: a noun takes an apostrophe only when it owns the thing named next. When two owners sit side by side, joined by “and”, and own separately, as in Ana’s and Leo’s logbooks, what's owned comes after the pair, so split it first (Ana’s logbooks and Leo’s logbooks); a later section covers pairs. Grammar books call a noun that owns something a possessive; this lesson calls it an owner, and a plural that owns nothing a plain plural.
In the examples, the noun being tested is bold, and the word after it, which decides, is underlined.
To test a noun, put of between it and the next noun, and flip them: the keeper’s lamp becomes the lamp of the keeper. If the flipped version says what the sentence means, the noun owns, and it takes an apostrophe. If the word after the noun can't be owned at all, there's nothing to flip, and the noun takes no apostrophe:
| What comes after the noun | Apostrophe? | Example |
|---|---|---|
| a thing it owns | yes | the keeper’s lamp |
| a verb | no | the keepers trimmed |
| a word like in, of or during | no | the keepers in the tower |
| a comma or a period | no | the town thanked its keepers. |
Describing words can sit between an owner and what it owns. Skip past them to the noun they describe, and run the test on that:
A noun right before another noun looks like an owner, but it may not be one. Run the of test anyway.
The visitors of the hours isn't what the sentence means. The visitors spent the hours, so the hours own nothing. Visitors is followed by its verb, spent, so it owns nothing either. So don't add an apostrophe because another noun follows: ask whether the noun owns it.
Songs or song’s? The guide hummed the ______ sailors once sang on the dock.
Run the of test on this question: a noun right before another noun may not own it.
Practice problem
To improve exhibit signage, a museum curator collected comment cards from many visitors and counted the different _____ used to describe a new interactive display.
Which choice completes the text so that it conforms to the conventions of Standard English?
Once a noun owns something, the apostrophe's place says how many owners there are. Write the owner as it would be with no ownership, keeper or keepers, then add the apostrophe: one owner takes ’s, and several owners ending in -s take ’ after the s.
| One keeper | More than one keeper | |
|---|---|---|
| Owns nothing | keeper | keepers |
| Owns something | keeper’s | keepers’ |
The passage tells you how many owners there are: a, one, a single or a name for one; two, both, several, these or a number for more. In the examples, the word that gives the count is underlined.
The first example has one keeper and several lamps; the second has two keepers and one cottage. Count the owners, never the thing they own. What's owned has its own number, which the passage decides separately.
Island’s or islands’? The ferry links the three ______ harbors to the mainland.
Count the owners in this question: check that the noun in the blank owns the next noun, then count the owners the passage names.
Practice problem
The Juniper Chapel and the Riverside Chapel were built nearly a century apart, but a recent architectural survey identified similarities in the two ______ painted ceilings and carved doorways.
Which choice completes the text so that it conforms to the conventions of Standard English?
A few nouns are plural without an -s. They're already plural, so they take ’s, the same as one owner.
| One | More than one | More than one, owning |
|---|---|---|
| child | children | children’s |
| person | people | people’s |
| woman | women | women’s |
Childrens isn't a word, so childrens’ can't be right either.
When two owners are joined by “and”, the passage says whether they share. When they own separately, each name takes ’s. One ’s at the end of the pair says the two own it together.
When they own separately, the first owner's thing comes after the second name, so split the pair to test it: Ana’s logbooks and Leo’s logbooks.
When only pronouns change in the choices, that's the last lesson's question. Some apostrophe questions change a noun and a pronoun in the same blank. Settle the noun with this lesson and the pronoun with that one: its for one thing, their for more than one. The two rules run opposite: a noun takes an apostrophe to own, and its and their never do.
| Noun | Pronoun | |
|---|---|---|
| One owner | lighthouse’s | its |
| More than one owner | lighthouses’ | their |
As the last lesson showed, it’s means it is, they’re means they are, and there names a place.
This question changes a noun and a pronoun: settle the noun with this lesson, then the pronoun with the last one.
Practice problem
Urbanist Jane Jacobs argued that lively sidewalks can make city streets safer. In her book The Death and Life of Great American Cities, she describes “eyes on the street”—the idea that everyday passersby can discourage crime. The _____ appeal: it suggests that safety can emerge from ordinary routines rather than from constant surveillance.
Which choice completes the text so that it conforms to the conventions of Standard English?
Most of these questions change two words at once, usually two nouns. Don't fix one noun and copy its form onto the other: each noun gets its own test. Test one, cross out every choice that gets it wrong, then test the next among the choices that are left.
Keeper owns the logbooks, so it takes ’s. Logbooks is followed by a verb, fill, so it owns nothing. One phrase, two different forms.
The word after the last noun often sits after the blank, outside the choices, so always read past the blank. A noun can also own a noun that owns the next one. Then both take an apostrophe, each counted on its own:
The keepers own the logbooks (the logbooks of the keepers), and the logbooks own the covers (the covers of the logbooks).
Where do the apostrophes go? Rain had smudged the ______ ink (keeper, logbooks). One keeper wrote all the logbooks.
That makes one routine for every apostrophe question, the one the worked examples and the practice problems follow:
Run the routine on this question: test each noun on its own, and read past the blank.
Practice problem
At the city archive, volunteers digitize thousands of letters written by dockworkers during the 1910s. Notes in the ______ margins clarify unfamiliar slang and abbreviations.
Which choice completes the text so that it conforms to the conventions of Standard English?
In this question, two nouns change, the two owners have different numbers, and the second one's owned noun sits after the blank.
Worked example
Along Alaska’s Denali Fault, instruments detect thousands of tiny earthquakes each year—most too small to feel. Researchers archive every event in a single catalog. Patterns in the ______ timing, which can indicate where stress is accumulating.
Which choice completes the text so that it conforms to the conventions of Standard English?
catalogs entries reveal the quakes
catalog’s entries reveal the quakes
catalog’s entries reveal the quakes’
catalogs’ entries reveal the quake’s
Step 1
The choices change only catalog and quakes; entries and reveal are the same in all four. So test the two nouns that change, one at a time. Start with catalog. The word after it is entries, and the entries of the catalog is what the text means, so catalog owns them and takes an apostrophe. That rules out A.
How many catalogs? Researchers archive every event in a single catalog, so there's one owner: catalog’s. That rules out D, whose catalogs’ means several catalogs.
Step 2
Now quakes. It's the last word in the choices, and B leaves it plain: that's the trap. B tempts most, because nothing inside the choices follows quakes. But the word after it sits right after the blank: timing. The timing of the quakes is what the text means, since the patterns show when the quakes happen. So quakes owns timing and takes an apostrophe. B is out.
Step 3
The instruments detect thousands of tiny earthquakes each year, so the owners are many, and the apostrophe goes after the s: quakes’. C has catalog’s and quakes’. D fails here too, since quake’s would mean one quake. The answer is C.
Here two names are joined by “and”, and the passage says whether they share what they own.
Worked example
In 1915, chemist Alice Ball developed an injectable treatment for Hansen’s disease; two decades later, chemist Percy Julian completed the first total synthesis of the medicine physostigmine. Although achieved independently, _____ breakthroughs expanded the possibilities of pharmaceutical chemistry.
Which choice completes the text so that it conforms to the conventions of Standard English?
Ball and Julians’
Ball and Julian’s
Balls’ and Julians’
Ball’s and Julian’s
Step 1
The choices change the apostrophes on two names before breakthroughs. Each name is one person, chemist Alice Ball and chemist Percy Julian, so neither can take ’ after an s, which would mean several owners. Julians’ in A and Balls’ and Julians’ in C would mean several people named Julian or Ball, so A and C are out.
Step 2
B and D both treat each name as one person, so the question is where the ’s goes. B puts one ’s at the end of the pair, which says Ball and Julian share the breakthroughs, as if they made them together. B tempts most, because it's shorter and reads smoothly. But the breakthroughs were achieved independently: Ball's in 1915, Julian's two decades later. The two own them separately, so B is out.
Step 3
When two owners own separately, each name takes ’s. Split the pair, as step 1 of the routine says: Ball’s breakthroughs and Julian’s breakthroughs. The answer is D.
These five questions mix the cases, so run the whole routine on each one: look at the word after each noun, count the owners, and settle any pronoun.
Practice problem
At the community greenhouse, volunteer ______ during open hours, offering quick tips on plant care to anyone who stops by.
Which choice completes the text so that it conforms to the conventions of Standard English?
Practice problem
The park installed new signs near the _____ to remind visitors to keep the area clean.
Which choice completes the text so that it conforms to the conventions of Standard English?
Practice problem
In a music workshop, the instructor asked students to compare two drummers: one playing on a small stage, the other playing in the hallway. The rhythm exercise is identical for both _____ locations.
Which choice completes the text so that it conforms to the conventions of Standard English?
Practice problem
Several local theaters in a city share one website for purchasing tickets; as a result, the _____ has made it easier for patrons to compare showtimes.
Which choice completes the text so that it conforms to the conventions of Standard English?
Practice problem
A culinary researcher found a handwritten recipe for a fruit tart written by a single pastry chef. The researcher also interviewed several bakery teams that make the same tart today. The similarity between the ______ methods suggests that the tart’s preparation has remained largely unchanged.
Which choice completes the text so that it conforms to the conventions of Standard English?
Finish the lesson
Finish the remaining questions correctly to complete this lesson.
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