use Roman; while () { chomp; last if (/^$/); my ($key, $data) = split(/\s+/, $_, 2); $key =~ s/([a-z])/roman(1+ord($1)-ord('a'))/eg; print join("\t", $key, $data), "\n"; } exit; __DATA__ a Johan b Gambolputty c von Haukopft d-y (much deleted) z of Ulm #### i Johan ii Gambolputty iii von Haukopft iv-xxv (much deleted) xxvi of Ulm