- (id)initWithName:(NSString *)_name 
               age:(NSNumber *)_age 
            gender:(Gender)_gender 
           classes:(NSArray *)_classes 
            salary:(NSNumber *)_salary  
   areaOfExpertise:(NSString *)_areaOfExpertise
{
   if ((self = [super init])) {
      name = _name;
      age = _age;
      gender = _gender;
      classes = _classes;
      salary = _salary;
      areaOfExpertise = _areaOfExpertise;
   }
   return self;
}
