Sub AddText(oSh As Shape)

Dim sTemp As String

' Pick up any existing text
' in the shape so we can use it
' as the default text in the next step
sTemp = oSh.TextFrame.TextRange.Text

' Get the new text:
sTemp = InputBox("Enter new text (or just a space to delete the text", "Edit text", sTemp)

' If there's any text, apply it to the shape
' To remove text from the shape, enter just a space
If Len(sTemp) > 0 Then
    oSh.TextFrame.TextRange.Text = sTemp
End If

' refresh the slide
SlideShowWindows(1).View.GotoSlide ( _

End Sub