The following VBA example applies bold formatting and underlining to the third paragraph.
Sub Test()
Dim t As Text
Dim s As Shape
Dim d As Document
Dim strText As String
strText = "This is a paragraph. " & vbCr & _
"This is a paragraph. " & vbCr & _
"This is a paragraph. " & vbCr & _
"This is a paragraph. " & vbCr & _
"This is a paragraph."
Set d = CreateDocument
Set s = d.ActiveLayer.CreateParagraphText(2, 2, 8, 8, strText)
Set t = s.Text
t.Story.Paragraphs.Item(3).Bold = True
t.Story.Paragraphs.Item(3).Underline = cdrDoubleThinFontLine
End Sub