static void Main(string[] args)
        {
            var p1 = new Person("Almila", "EROL");
            var s1 = new Student("Yunus", "EROL", "100");
            var t1 = new Teacher("Yasemin", "UZUN", "Math");

            p1.Intro();
            s1.Intro();
            t1.Intro();
            t1.Teach();
        }