How to show multiple questions display in one by one in c# windows application by using timer

using System.Threading;

// Somewhere in your Form, for example in Form_Load event:
new Thread(new ThreadStart(delegate {
    var d = new setLabelTextDelegate(setLabelText);
    label1.Invoke(d, new object[] { "string 1" });
    Thread.Sleep(3000); // sleep 3 seconds
    label1.Invoke(d, new object[] { "string 2" });
    Thread.Sleep(5000); // sleep 5 seconds
    label1.Invoke(d, new object[] { "string 3" });
})).Start();

private delegate void setLabelTextDelegate(string text);
private void setLabelText(string text)
{
    this.label1.Text = text;
}