Three Promoted to Professor - Jennifer Borton (psychology), Sally Cockburn (mathematics) and Julio Videras (economics) were promoted to the rank of professor.
Use the apostrophe to indicate possession and to mark omitted letters in contractions. Writers often misuse apostrophes when forming plurals and possessives. The basic rule is quite simple: use the apostrophe to indicate possession, not a plural. Yes, the exceptions to the rule may seem confusing: hers has no apostrophe, and it's is not possessive. Nevertheless, with a small amount of attention, you can learn the rules and the exceptions of apostrophe use.
SOURCE: Nesbitt-Johnston Writing Center