JokeAboutMice.cs

static void Main() {
    foreach (var line in TellJokeAboutMice())
    {
        Console.WriteLine(line);
    }
}

private static IEnumerable<string> TellJokeAboutMice()
{
    yield return "MR MICE.";
    yield return "MR NOT.";
    yield return "OSMR! CM EDBD FEET?";
    yield return "LIB! MR MICE!";
    yield break;
}