Who´s or Whose
Whose or Who's ? Whose is the possessive form of who (or, occasionally, which ). It means "belonging to whom or which." Who's is a contraction of who is or who has. Notice the apostrophe replacing the missing letters. Incorrect: Who's department do you work for? Correct: Whose department do you work for? Correct: Who's coming to visit tomorrow? http://www.bristol.ac.uk/arts/exercises/grammar/grammar_tutorial/page_57.htm