ACT English: Apostrophes—Possession vs. Contraction (Know the Difference)

Use 1 (Possession): Shows that something belongs to someone. Examples: "John's book," "the cat's toy," "the students' test." Rules: singular noun+apostrophe+s (John's); plural ending in s+apostrophe (students'). Pronouns do NOT use apostrophes for possession (his, hers, its, theirs—no apostrophes). Use 2 (Contraction): Combines two words. Examples: "it's" (it is), "don't" (do not), "she's" (she is). The apostrophe replaces the missing letter(s). Quick test: If you can replace it with two words, it is a contraction and needs an apostrophe. If it is possession (belongs to), use apostrophe+s (or just apostrophe for plural).

Common error: "its" vs. "it's." "Its" is possessive (the cat wagged its tail). "It's" is "it is" (It's sunny today).

Rule 1 (Singular): Add apostrophe+s. "The dog's bone," "James's car." (Even if the name ends in 's', add 's.) Rule 2 (Plural ending in 's'): Add apostrophe only. "The dogs' toys" (multiple dogs). Rule 3 (Plural NOT ending in 's'): Add apostrophe+s. "Children's games," "men's room." Rule 4 (Compound): Apostrophe goes on the last noun. "John and Mary's house" (shared). "John's and Mary's houses" (separate). The trickiest: plural possessives. "The girls' soccer team" (team belongs to multiple girls). "The girl's soccer team" (team belongs to one girl).

Pronouns (possessive, no apostrophe): his, hers, its, ours, yours, theirs. Never use apostrophe with these.

Sentence 1: "The cat's toy is lost." Correct. Singular possession (toy belongs to the cat). Sentence 2: "Its color is blue." Correct. "Its" = possessive pronoun (no apostrophe). Sentence 3: "It's raining outside." Correct. "It's" = "it is." Sentence 4 (Error): "The students' uniforms are ready." Correct (plural possession—uniforms belong to multiple students). Sentence 5 (Error): "Johns' house is big." Incorrect. Should be "John's house." (Singular name, add apostrophe+s, even though it ends in 's'.) Mark every apostrophe in practice tests and verify it is either possession or contraction.

Build this habit until apostrophe usage becomes automatic.

Apostrophe errors appear in 1-2 ACT English questions per section. They test two distinct uses: possession and contraction. Mastering both uses eliminates a consistently tested grammar point and yields 1-2 guaranteed points.

Learn the possession and contraction rules once. By test day, you will spot apostrophe errors instantly and correct them.