how do you add a phrase to a field if the filed is blankl,

What "phrase" do you mean? A Comment? A value?

also, can you have
a notifiction sent to you when a date on a spreadsheet has expired?
Maybe you can apply an open event (date to be tested being say in F1):

Private Sub Workbook_Open()
If Range("F1") < Date Then
MsgBox "Date expired"
End If
End Sub

Regards,
Stefi