title: Previous month with month name in google sheets
body: <p>I have a month "August" and need a formula that gives me the name of the month before. </p>
  
  <pre><code>=TEXT(EDATE("August"; -1); "MMMM")
  </code></pre>
  
  <p>This does not work, as EDATE expects a DATE(). Can anyone advice?</p>