Add Method (FormFields Collection) Example
This example adds a check box at the end of the selection, gives it a name, and then selects it.
Selection.Collapse Direction:=wdCollapseEnd
Set ffield = ActiveDocument.FormFields _
.Add(Range:=Selection.Range, Type:=wdFieldFormCheckBox)
With ffield
.Name = "Check_Box_1"
.CheckBox.Value = True
End With