List listx = new List();
// Set the space between the markers and list content to 25 DIP.
listx.MarkerOffset = 25;
// Use uppercase Roman numerals.
listx.MarkerStyle = TextMarkerStyle.UpperRoman;
// Start list numbering at 5.
listx.StartIndex = 5;

// Create the list items that will go into the list.
ListItem liV = new ListItem(new Paragraph(new Run("Boron")));
ListItem liVI = new ListItem(new Paragraph(new Run("Carbon")));
ListItem liVII = new ListItem(new Paragraph(new Run("Nitrogen")));
ListItem liVIII = new ListItem(new Paragraph(new Run("Oxygen")));
ListItem liIX = new ListItem(new Paragraph(new Run("Fluorine")));
ListItem liX = new ListItem(new Paragraph(new Run("Neon")));

// Finally, add the list items to the list.
listx.ListItems.Add(liV);
listx.ListItems.Add(liVI);
listx.ListItems.Add(liVII);
listx.ListItems.Add(liVIII);
listx.ListItems.Add(liIX);
listx.ListItems.Add(liX);