There are likely many variations on marking matches, but here's one straightforward method. In this example, my long list is in column A1..A100, and my short list is in E1..E10. I place this function in cell B1:
@IF(@ISERR(@MATCH(A1,$A:$E$1..$E$10,0)),"","Match")
You would modify the function to fit the blocks where your lists are. Then copy that function parallel to long list (in my case, into cells B2..B100).
The function tests whether the parallel cell in column A matches a cell in E1..E10. If not, it returns the empty string. But if there is a match, it returns the word "Match." You can then go down column B to find cells in column A that match the short list.
An alternative macro could be written that would instead alter each cell in the long list where a match occurs, e.g., by making it bold, or italic, or changing the background color or foreground color.
Charlie