See join for joining array elements into a string.

See map for converting array elements into other.

Basically, your conversion will look like this:

my @array = qw(balack white green red);

my @tagged_array = map { ... } @array;
my $result = join ... @tagged_array;

print $result;
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Of course, I've left out the interesting parts, but as you don't show the code you've written, I can't help you more.

For reference, see the documentation of join and map.

foreach (@array) {
  $_= '<tag>' . $_ . '</tag>'
}
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my @newarray= map { '<tag>' . $_ . '</tag>' } @array;
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UPDATE: misread your question. Should you ever need the tags in the array itself, this would be the answer ;-)

Do you like XML?

use XML::Simple;

my @array = qw(balack white green red);

print XMLout(\@array, RootName => undef, NoIndent => 1);

__OUTPUT__
<anon>balack</anon><anon>white</anon><anon>green</anon><anon>red</anon
+>

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