Combine each element to another.

gistfile1.php

<?php

$array = ["lot's", "of", "elements", "…"];
$allConcatinations = [];
for ($a=0; $a<count($array); $a++) {
    	for ($b=$a+1; $b<count($array); $b++) {
    		array_push($allConcatinations, $array[$a]." ".$array[$b]);
	}
}