Array_combine - объединение массивов для дальнейшего поиска по ключу

            $massiv=array_combine($oshibki,$slova);
            print_r($massiv);

$slova[] :
My Array ( [0] => 1.21 gigawatts [1] => 6 feet of snow [2] => 8th chevron [3] => abide with me [4] => abra cadabra [5] => absolute zero [6] => al capone [7] => alabama [8] => april may [9] => austin [10] => belt up [11] => beyond me [12] => blue sky [13] => bone dry [14] => call me [15] => dust up [16] => gung ho [17] => hug me [18] => june july [19] => many me [20] => pick my [21] => tune in ) 
$oshibki[] : 
My Array ( [0] => 13 [1] => 13 [2] => 11 [3] => 11 [4] => 11 [5] => 11 [6] => 9 [7] => 6 [8] => 6 [9] => 6 [10] => 6 [11] => 6 [12] => 6 [13] => 5 [14] => 5 [15] => 5 [16] => 4 [17] => 4 [18] => 4 [19] => 4 [20] => 4 [21] => 4 )

array(
13 => array ("1.21 gigawatts [1]", "6 feet of snow"),
11 => array ("8th chevron", "abide with me", "abra cadabra"),
...//ну и т.д.
)

<?php
$slova= Array ( 0 => '1.21 gigawatts', 1 => '6 feet of snow', 2 => '8th chevron', 3 => 'abide with me', 4 => 'abra cadabra', 5 => 'absolute zero', 6 => 'al capone', 7 => 'alabama', 8 => 'april may', 9 => 'austin', 10 => 'belt up', 11 => 'beyond me', 12 => 'blue sky', 13 => 'bone dry', 14 => 'call me', 15 => 'dust up', 16 => 'gung ho', 17 => 'hug me', 18 => 'june july', 19 => 'many me', 20 => 'pick my', 21 => 'tune in' ) ;
$oshibki = Array ( 0 => 13, 1 => 13, 2 => 11, 3 => 11, 4 => 11, 5 => 11, 6 => 9, 7 => 6, 8 => 6, 9 => 6, 10 => 6, 11 => 6, 12 => 6, 13 => 5, 14 => 5, 15 => 5, 16 => 4, 17 => 4, 18 => 4, 19 => 4, 20 => 4, 21 => 4 );
 
$new_arr=array();
foreach($oshibki as $k => $v){
    
    $new_arr[$v][]=$slova[$k];
}
echo "<pre>";
print_r($new_arr);
echo "</pre>";
?>