As part of a much larger text calculation (in the style of a merge letter style solution) , I am trying to create a custom function that will substitute a tag/placeholder such as <<a or an>> with either "a" or "an" in the final calculation, which I think will need to based on a pre-defined list of words that would require one or the other. From a grammar perspective, the use of the articles "a" or "an" is irregular, as it is based on if the subsequent word (most of the time at least) has a vowel sound (e.g., both "university" and "undone" start with the letter "u", but each requires a different article because one has a vowel sound when said aloud and the other doesn't. So, I would expect to have to supply 2 lists of words within the custom function that (which I would update regularly), unless someone happens to know another way to do this.
Given a text calculation that might read something like: "The client's reading performance was found to be at <<a or an>> eighth grade level, while his math calculation skills were found to be at <<a or an>> first grade level. " The first placeholder would be "an" and the second would be "a".