Excel VBA：如果A2 =“a”，“b”，“c”等......那么B2 =“aa”？

I'm attempting to take the text in each cell of column A and assign a value to each cell in column B depending on the text in column A. For example, I have a list of versions that are identified by four-letter abbreviations of cities, and all of those versions are regionally assigned to different factories to be produced. So let's say I have an "AUST", "DAFW", "HOUS", and more versions all assigned to the location of "ARLINGTON". How would I most concisely use VBA to automate that once I have all the versions plugged in? Something likeI'm attempting to take the text in each cell of