use strict;
use warnings;

my @file;
my @stichworte;
open(FILE1, $ARGV[0])|| die "could not open file";
while (<FILE1>) {

push @stichworte, $1 if /^(\w+),/;
}
close FILE1;

# Regex zusammenbasteln
my $verodert = join '|', @stichworte;


open(FILE2, $ARGV[1])|| die "could not open file";

while (<FILE2>) { # aus Dateien aus @ARGV

s~($verodert)~<mark>$1</mark>~gi;
push @file, $_;
print @file;

}

close FILE2;