Despite decades of study including time spent at universities, writers and journalists often misuse the apostrophe. Here are six tips:
1. Use an apostrophe and ‘s’ to form the possessive case of singular nouns (a year’s work). [For plural nouns in the possessive case, use “two years’ work”.]
2. Same goes for the possessive case of indefinite pronouns (anyone’s guess).
3. Personal pronouns do not require an apostrophe (your/yours).
4. To form the possessive of compound nouns, make the last element the possessive (daughter-in-law’s cooking or daughters-in-laws’ cooking).
5. To show joint ownership, make the last name possessive (Mark and Jane’s villa).
6. To show separate ownership, make each name possessive (Mark’s and Ben’s hats).
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