SAT Reading & Writing – Standard English Conventions
Plurals and Possessives
Correctly forming plural nouns and showing ownership with apostrophes
Plurals and Possessives questions test your ability to distinguish between plural forms (showing multiple items) and possessive forms (showing ownership), correctly use apostrophes to indicate possession, form irregular plurals, and recognize when no apostrophe is needed. On the SAT, you'll identify whether a noun should be plural, possessive, or both, and place apostrophes correctly.
Success requires understanding the difference between plural and possessive meanings, knowing apostrophe placement rules for singular and plural possessives, recognizing irregular plural forms, and identifying when apostrophes are incorrectly added to simple plurals. These mechanics skills aren't just punctuation rules—they represent precise expression essential for academic writing, professional communications, clear ownership indication, and any context where apostrophe errors signal carelessness or confusion about meaning.
Understanding Plurals and Possessives
Basic Plural Formation
Simple plurals show multiple items—NO apostrophe.
Nouns ending in s, x, z, ch, sh: Add -es (box → boxes, church → churches)
Nouns ending in consonant + y: Change y to -ies (city → cities, baby → babies)
Nouns ending in vowel + y: Just add -s (boy → boys, key → keys)
KEY RULE: Plural nouns NEVER use apostrophes (❌ apple's for sale ✓ apples for sale)
Possessive Formation (The Main Focus!)
Possessives show ownership—ALWAYS use apostrophe.
Plural ending in -s: Add ' only (the cats' toys, the students' project)
Plural NOT ending in -s: Add 's (the children's books, the women's rights)
Remember: It's = it is / its = possessive (The dog wagged its tail)
They're vs. their: They're = they are / their = possessive (their books)
Common Confusion: Its vs. It's
This is THE most tested possessive issue on the SAT.
Example: It's raining. (It is raining.)
Its (no apostrophe): Possessive form showing ownership
Example: The dog wagged its tail. (The tail belongs to the dog.)
Test: If you can replace with "it is" or "it has," use it's. Otherwise, use its.
Other Common Possessive Confusions
Similar pairs that test possessive vs. contraction knowledge.
You're vs. your: You're = you are / your = possessive
Who's vs. whose: Who's = who is/has / whose = possessive
Pattern: Contractions use apostrophes; possessive pronouns DON'T
Exception: Regular possessive nouns DO use apostrophes (Mary's book)
Essential Plural and Possessive Strategies
Ask "Multiple or Ownership?"
Multiple items: Use plural form, NO apostrophe
Ownership/belonging: Use possessive with apostrophe
Example: "The students books" → Do we mean multiple students or students' books?
Test: Can you insert "of the" or "belonging to"? If yes, use possessive.
Use the Substitution Test for Contractions
For it's/its: Replace with "it is" or "it has"
If it works: Use it's (with apostrophe)
If it doesn't work: Use its (no apostrophe, possessive)
Same test: Works for they're/their, you're/your, who's/whose
Determine Singular vs. Plural Possessive
One owner: Singular possessive → add 's (the student's essay)
Multiple owners: Plural possessive → add ' after s (the students' essays)
Irregular plurals: Add 's (children's, women's, people's)
Check context: How many owners? One cat's toy vs. three cats' toys
Watch for Unnecessary Apostrophes
Common error: Adding apostrophes to simple plurals
Wrong: "Apple's for sale" "The 1990's" "Two DVD's"
Right: "Apples for sale" "The 1990s" "Two DVDs"
Remember: Plurals = NO apostrophe unless showing possession
Common Pitfalls & Expert Tips
❌ Confusing "its" and "it's"
This is the #1 tested error! "Its" (no apostrophe) = possessive. "It's" (apostrophe) = "it is" or "it has." Test by substitution!
❌ Adding apostrophes to simple plurals
"The student's are studying" is WRONG. "Students" (plural) needs NO apostrophe. Only use apostrophes for possession or contractions.
❌ Misplacing apostrophe on plural possessives
"The students' books" (books belonging to multiple students) needs apostrophe AFTER the s. "The student's books" means one student's books.
❌ Treating possessive pronouns like regular nouns
Possessive pronouns (its, theirs, yours, hers, whose) NEVER take apostrophes. Only possessive nouns do (Mary's, the dog's).
✓ Expert Tip: Use the "it is" test
Whenever you see its/it's, substitute "it is" or "it has." If the sentence makes sense, use "it's." If not, use "its."
✓ Expert Tip: Count the owners
For possessives, determine if there's one owner (add 's) or multiple owners (add ' after the s). Context tells you which!
✓ Expert Tip: Remember possessive pronouns are exceptions
Its, theirs, yours, hers, whose, ours—none of these possessive pronouns use apostrophes. They're already possessive!
Fully Worked SAT-Style Examples
Passage:
The company announced that ______ expanding operations to three new countries next year.
Question:
Which choice completes the text so that it conforms to the conventions of Standard English?
Answer Choices:
A) its
B) it's
C) its'
D) it
Correct Answer: B
Substitution test: Try replacing the blank with "it is": "The company announced that it is expanding operations..." This makes perfect sense!
Analysis: The sentence needs a contraction meaning "it is." "It's" = "it is" or "it has." "Its" = possessive (belonging to it). Here we need the contraction.
Why B is correct: "It's" with apostrophe is the contraction of "it is," which fits the sentence perfectly: "that it is expanding operations."
Why A is wrong: "Its" (no apostrophe) is possessive, meaning "belonging to it." You can't say "The company announced that belonging to it expanding..." Makes no sense.
Why C is wrong: "Its'" is not a real word. Possessive pronouns never take apostrophes, and "its" is already possessive.
Why D is wrong: "It" alone doesn't work: "The company announced that it expanding..." Missing the verb "is."
Passage:
The ______ findings revealed significant correlations between diet and longevity.
Question:
Which choice completes the text so that it conforms to the conventions of Standard English?
Answer Choices:
A) researchers
B) researchers'
C) researcher's
D) researchers's
Correct Answer: B
Meaning analysis: The sentence discusses "findings" that belong to "researchers" (multiple people). We need possessive to show the findings belong to the researchers.
Ownership test: Can we say "the findings OF the researchers"? Yes! This indicates we need possessive form, not simple plural.
Why B is correct: "Researchers'" is plural possessive (apostrophe after the s), indicating findings belonging to multiple researchers. Context suggests a research team, not one person.
Why A is wrong: "Researchers" is simple plural with no possession. "The researchers findings" doesn't show that findings belong to them—needs apostrophe.
Why C is wrong: "Researcher's" is singular possessive (one researcher). While grammatically possible, "findings" (plural) suggests multiple researchers conducted the study.
Why D is wrong: "Researchers's" is not correct form. Plural nouns ending in s take apostrophe alone (researchers'), not 's.
Passage:
The students were proud of ______ performance in the national debate competition.
Question:
Which choice completes the text so that it conforms to the conventions of Standard English?
Answer Choices:
A) there
B) their
C) they're
D) theirs
Correct Answer: B
Meaning analysis: The sentence discusses a "performance" that belongs to "the students." We need the possessive form to show ownership.
Three options breakdown: "There" = location/place. "Their" = possessive (belonging to them). "They're" = "they are" contraction.
Why B is correct: "Their" is the possessive form, meaning "belonging to them." The performance belongs to the students, so we need possessive "their."
Why A is wrong: "There" indicates location or existence ("over there," "there is"). Doesn't show ownership: "proud of there performance" makes no sense.
Why C is wrong: "They're" = "they are." Test by substitution: "proud of they are performance" is nonsensical.
Why D is wrong: "Theirs" is possessive pronoun used independently ("That book is theirs"), not before a noun. Can't say "theirs performance."
Passage:
Dr. Martinez specializes in studying ______ migration patterns across North America.
Question:
Which choice completes the text so that it conforms to the conventions of Standard English?
Answer Choices:
A) bird's
B) birds
C) birds'
D) birds's
Correct Answer: C
Context analysis: The sentence discusses "migration patterns" that belong to birds. "Migration patterns" is plural, suggesting multiple birds, not one bird. We need possessive (patterns OF the birds).
Number determination: Since we're discussing general migration patterns across a continent, context indicates multiple birds (plural), not a single bird.
Why C is correct: "Birds'" is plural possessive (apostrophe after the s), showing that migration patterns belong to multiple birds. Appropriate for studying bird species generally.
Why A is wrong: "Bird's" is singular possessive (one bird's patterns). Studying one bird's migration pattern across North America doesn't make logical sense.
Why B is wrong: "Birds" is simple plural with no possession. "Studying birds migration patterns" doesn't show that patterns belong to birds—needs apostrophe.
Why D is wrong: "Birds's" is incorrect form. Plural nouns ending in s add only apostrophe (birds'), not 's.
Passage:
The new policy aims to improve ______ access to healthcare services in rural areas.
Question:
Which choice completes the text so that it conforms to the conventions of Standard English?
Answer Choices:
A) childrens'
B) children's
C) childrens
D) children
Correct Answer: B
Irregular plural rule: "Children" is already plural (irregular plural of "child"). It doesn't end in -s, so when making it possessive, we add 's just like a singular noun.
Possession test: The sentence discusses "access" belonging to children (access OF children). This indicates we need possessive form.
Why B is correct: "Children's" adds 's to the irregular plural "children." Rule: irregular plurals not ending in -s take 's for possessive (children's, women's, people's, mice's).
Why A is wrong: "Childrens'" would be used if the plural were "childrens" (which it's not). "Children" is already plural, so we add 's, not just apostrophe.
Why C is wrong: "Childrens" is not a word. The plural of "child" is "children," not "childrens."
Why D is wrong: "Children" is plural but not possessive. "Improve children access" doesn't show that access belongs to children—needs apostrophe.
Plurals and Possessives Quick Reference
| Form | Rule | Example |
|---|---|---|
| Simple Plural | Add -s or -es (NO apostrophe) | cats, boxes, babies |
| Singular Possessive | Add 's | the cat's toy, James's book |
| Plural Possessive (ends in -s) | Add ' only | the cats' toys, the students' work |
| Irregular Plural Possessive | Add 's | children's, women's, people's |
| It's vs. Its | It's = it is; Its = possessive | It's raining. The dog wagged its tail. |
| Their/They're/There | Their = possessive; They're = they are; There = location | Their books. They're here. Over there. |
Plural and Possessive Testing Checklist
Decision Process
1. Multiple items or ownership?
2. If ownership, one or many owners?
3. For contractions, test substitution
4. Check if irregular plural
Common Contractions
It's = it is or it has
They're = they are
You're = you are
Who's = who is or who has
Plurals and Possessives: Mastering Apostrophes and Ownership Indicators
Plurals and Possessives questions assess your ability to distinguish between plural forms indicating multiple items and possessive forms indicating ownership, correctly place apostrophes for singular and plural possession, form irregular plurals, and recognize common contraction versus possessive confusions like its/it's and their/they're—fundamental mechanics skills transcending standardized testing to become essential for clear academic writing, professional communications, precise ownership indication, and any context where apostrophe errors signal carelessness or confusion about basic grammar conventions. The SAT tests this competency because proper plural and possessive usage represents basic writing proficiency: understanding that simple plurals never use apostrophes despite being common in informal contexts like grocery store signs, recognizing that possessive forms require apostrophes to show ownership relationships, knowing placement rules that distinguish singular possessives (add 's) from plural possessives (add ' after s), mastering the most frequently confused pairs like its/it's where contractions use apostrophes but possessive pronouns don't, and developing sensitivity to how apostrophe errors undermine writing credibility and sometimes change meaning entirely. When ensuring "the text conforms to conventions of Standard English," you practice the same mechanical awareness required for academic papers where apostrophe errors mark careless editing, professional documents where possessive mistakes damage credibility with clients and colleagues, technical communications where precision in all details including apostrophes reflects overall reliability, and any formal writing where mechanical correctness serves as a baseline expectation for educated writers. Plurals and possessives follow systematic, learnable rules: determine whether you're indicating multiple items (plural, no apostrophe) or ownership (possessive, with apostrophe), count the owners to decide between singular possessive (one owner, add 's) and plural possessive (multiple owners, add ' after s), handle irregular plurals like children/women/people by adding 's since they don't end in s, master contraction-possessive distinctions by using substitution tests (if you can replace with "it is" use it's; otherwise use its), and remember that possessive pronouns (its, theirs, yours, whose, hers) never take apostrophes despite showing ownership because they're already possessive forms. Every time you correctly place apostrophes in possessives while avoiding them in simple plurals, distinguish its from it's through substitution testing, or form irregular plural possessives correctly, you're exercising the mechanical awareness that enables not just error-free but professionally credible writing where proper apostrophe usage signals competence and ensures readers understand relationships of ownership and multiplicity without confusion about meaning or grammatical correctness.