#print When you want to match one of a few specific characters, and not just anything, the pattern is similar to that used in file names. That is, [abc] matches the letters 'a', 'b', or 'c', but nothing else. Try this sequence and note what happens: ex lines 1,$p 1s/[123]/9/ 2s/[123]/9/ 1,$p wq ready (Remember that you can use '%' to abbreviate '1,$p'.) #create Ref 599 948 #create lines 519 348 #user #cmp lines Ref #log #next 33.2b 5