参考网上例子，在PPT中批量设置m3的3为上标的VBA

Sub Replace_m3_to_supscript()
    Dim sld As Slide
    Dim shp As Shape
    Dim txtRng As TextRange
    Dim i As Long
    For Each sld In ActivePresentation.Slides
        For Each shp In sld.Shapes
            If shp.HasTextFrame And shp.TextFrame.HasText Then
                Set txtRng = shp.TextFrame.TextRange
                For i = 1 To Len(txtRng)
                    If Mid(txtRng, i, 1) = "m" Then
                        If Mid(txtRng, i + 1, 1) = "3" Then
                            txtRng.Characters(i + 1, 1).Font.Superscript = msoTrue
                        End If
                    End If
                Next i
            End If
        Next shp
    Next sld
End Sub

如要设置下标，则改txtRng.Characters(i + 1, 1).Font.Subscript = msoTrue