ThreadingEx03.cs

static void Main(string[] args)
{
    Thread t1 = new Thread(MyBackgroundTask);
    Thread t2 = new Thread(MyBackgroundTask);
    Thread t3 = new Thread(MyBackgroundTask);

    t1.Start("X");
    t2.Start("Y");
    t3.Start("Z");

    t1.Join();
    t2.Join();
    t3.Join();

    for (int i = 0; i < 500; i++)
    {
        Console.Write(".");
    }
}