how to add space when concanating two Strings in .net?

using System;

class NameExample

{

    public static void Main()

    {

        string fName = "Sandeep";

        string lName = "Singh";

        string fullName = string.Format("{0} {1}", fName, lName);

        Console.WriteLine(fullName);

        Console.ReadKey();

    }

}