Making a scrabble cheat sheet, combine two cells, changing color is they match, then...

I have a goal of learning all three letter words acceptable in scrabble. I manipulated the list down to four columns and want to make it three columns.
My approach is to learn mnemonics. Currently in rows, first column is the two letters that start the three letter words I am memorizing, the second column is all the letters that when added to the column a (as the third letter) make an acceptable word. Column 3 is the letters that I need to learn for those first two letters. Column four is the phrase I am using to memorize. What I want to do have is Columns a and b combined and all the letters that were in b, made red. Then I would like to have the "mnemonics" column have any letter Upper Case that is in the 'all acceptable letter, regardless of color'. If it not, then lower case. This should help.

BTW, first time posting in any forum of any type. Hello.