- http_build_query: documentation ( source)
<?php
$array = array('t'=>'e', 's'=>'t', 'te' =>array('st' => '!!!!'));
echo http_build_query($array);
$array = array('t'=>'e', 's'=>'t', 'te' => http_build_query(array('st' => '!!!!')));
echo http_build_query($array);