Task 10 Middle Managers Clothing manufacturer has openings for middle managers with intermediate computer experience. Must have at least three years of background supervising personnel in factory setting. On-the-line experience is a plus. Knowledge of English is required. Salary is commensurate (成适当比例) with experience and abilities. How many years of experience in supervising personnel must applicants have Applicants must have ______ years of experience in supervising personnel.