static void Main(string[] args) { var s = new Student("Alex"); University university = new University("CH.U.I."); university.AddStudent(new Student("Andrew Kostenko", new Knowledge(5))); university.AddStudent(new Student("Julia Veselkina", 5)); university.AddStudent(new Student("Maria Perechrest", 3)); Internship internship = new Internship("Interlink"); internship.CreatingListOfIntern(university); Console.WriteLine("List of internship's students:"); Console.WriteLine(internship.GetStudents()); Console.ReadKey(); }