SAT Apostrophe Mastery: Possessives vs. Plurals and the Its/It's Rule

Add 's to show possession (the student's book, the students' books, John's pen). Plural nouns without possession use no apostrophe (five books, multiple options). The single most common SAT error confuses plural with possessive by adding an unnecessary apostrophe. "The cat's are sleeping" should be "The cats are sleeping." The apostrophe is wrong.

Contractions (don't, can't, it's=it is) also use apostrophes, which creates confusion. However, possessive pronouns (his, her, its, whose) NEVER use apostrophes. This exception trips many students because "it's" looks like it should be possessive.

Try substituting "it is" into the sentence. If it makes sense, use "it's" (it is). If not, use "its" (possessive). Example: "The dog wagged its tail" becomes "The dog wagged it is tail"—wrong. Use "its." Example: "It's raining" becomes "It is raining"—correct. Use "it's." The substitution test eliminates all its/it's confusion instantly.

Three micro-examples: "The company announced its earnings"=its (possessive, "the company's earnings"). "It's a beautiful day"=it's (it is). "The tree lost its leaves"=its (possessive, "the tree's leaves").

Trap 1: Plural names and decades—"the 1990's music" should be "the 1990s music." Trap 2: Possessive pronouns—"your," "their," "whose" never take apostrophes. Trap 3: Acronyms—"PhDs work here" not "PhD's work here." Build the habit of asking "Am I showing possession or just pluralizing?" before every apostrophe.

Practice spotting these errors in reading passages. When you see an apostrophe, verify it is either a contraction or a possessive, not a misplaced plural marker. This habit transfers to writing questions where you identify similar errors.

Day 1-2: Practice its/it's with 20 sentences each day. Day 3-4: Practice plurals vs. possessives with 15 sentences each day. Day 5: Mixed apostrophe errors across all categories, 25 sentences. Aim for 100% accuracy. Apostrophe errors are entirely preventable with focused practice.

After this five-day protocol, apostrophe errors should disappear from your writing and reading comprehension entirely. The investment in these five days pays dividends for every test you take, not just the SAT.