Sub Demo()
Application.ScreenUpdating = False
Dim StrFnd As String, i As Long
StrFnd = "One,Two,Three"
With ActiveDocument.Range.Find
.ClearFormatting
.Replacement.ClearFormatting
.Replacement.Text = "^&"
.Replacement.Font.Underline = wdUnderlineSingle
.Forward = True
.Wrap = wdFindContinue
.MatchCase = True
.MatchWholeWord = True
.MatchWildcards = False
.MatchSoundsLike = False
.MatchAllWordForms = False
For i = 0 To UBound(Split(StrFnd, ","))
.Text = Split(StrFnd, ",")(i)
.Execute Replace:=wdReplaceAll
Next
End With
Application.ScreenUpdating = True
End Sub