Thanks Charles

The dropdown I referred to is via Data Validation List. I don't
know if it's important, but the dropdown is comprised of merged
cells. If in the dropdown I select "Turning off the lights" from
the list, the macro reads the range's assigned value of 100 and
dictates the sentence "Be sure to turn off the lights." (It's a
silly example, I know.) What I need to happen-if possible-is for
the dropdown phrase to disappear once the speech is finished, so the
sentence is not read again the next time there is input in the
worksheet. My macro is as follows:

Private Sub Worksheet_Calculate()
With Application.Speech
Select Case Range("A1")
Case Is = 100: .Speak "Be sure to turn off the lights."
End Select
End With
End Sub

I am a novice at this, so thanks for bearing with me.

Michael