static void Main(string[] args) { Student[] students = new Student[] { new Student() { FirstName = "Kalin", LastName = "Javorov", Age = 29 }, new Student() { FirstName = "Genoveva", LastName = "Petrova", Age = 25 }, new Student() { FirstName = "Petar", LastName = "Dimitrov", Age = 24 }, new Student() { FirstName = "Penka", LastName = "Filipova", Age = 20 }, new Student() { FirstName = "Galia", LastName = "Hristova", Age = 29 }, }; var comparedStudents = students.OrderByNames().Select(s => new { Name = s.FirstName + " " + s.LastName, Age = s.Age }); var studentsByAge = students.Where(s => s.Age > 18 && s.Age < 24).Select(s => new { Name = s.FirstName + " " + s.LastName, Age = s.Age }); Console.WriteLine(string.Join(", ", comparedStudents)); Console.WriteLine(string.Join(", ", studentsByAge)); }