Pastebin to the Rescue

static void Main(string[] args)
{
    var index = 0;
    foreach (var result in Hello())
    {
        Console.WriteLine(result);
        index++;

        if (index >= 10)
        {
            break;
        }
    }

    Console.ReadLine();
}

private static IEnumerable<string> Hello()
{
    while (true)
    {
        yield return "Hello World";
    }
}