class Program
    {
        static void Main(string[] args)
        {
            string test = "test'abc";
            string a = HttpUtility.HtmlDecode(test);
            Console.WriteLine(a);
            test = "testΓabc";
            a = HttpUtility.HtmlDecode(test);
            Console.WriteLine(a);
            a = HttpUtility.HtmlDecode("a   r");
            Console.WriteLine(a);
            Console.Read();
        }
    }