The replies provided were fantastic.. I am not really sure if a bidirectional hash with key-value value-key combinations can also be considered and equally efficient in case you have a large amount of relations. Dear Monks please be free to criticize this, I aspire to learn by interaction.

This code here can let you treat all the right and left values as keys and as values of each other, then you may want to use the hash as a search dictionary:

#!/usr/local/bin/perl
#title "One to one relationship";
use strict;
use warnings;
use diagnostics;

my %hash;
while(<DATA>){
        next unless /"(\w+)".*"(\w+)"/gs;
        $hash{$1}=$2;
        $hash{$2}=$1;
        }

use Data::Dumper;
print Data::Dumper->Dump ([\%hash]);


__DATA__
"ger" <--> "german"
"ara" <--> "arabic"
"eng" <--> "english"
[download]

here's the output:

$VAR1 = {
          'arabic' => 'ara',
          'ara' => 'arabic',
          'ger' => 'german',
          'german' => 'ger',
          'english' => 'eng',
          'eng' => 'english'
        };
[download]