You are wrong in declaring the array:

perl -MData::Dumper -e "@arr=['a','b']; print Dumper (\@arr)"
$VAR1 = [
          [
            'a',
            'b'
          ]
        ];
[download]

You are declaring arrays with only one element which turns to be an anonyomous array.

Without getting deep in what your data means or meant to be used, you have to do something simple as:

perl -MData::Dumper -e "@arr1=qw(a b);@arr2=qw(c d);foreach (@arr1,@ar
+r2){print qq([$_]\n) }"
[a]
[b]
[c]
[d]
[download]

HtH
L*