how do I concatenate the string values of two arrays pairwise with PHP?

Question

So I have two arrays

Array
(
[0] => test
[1] => test 1
[2] => test 2
[3] => test 3
)

and

Array
(
[0] => test         


        

Answer 1

Assuming the two arrays are $array1 and $array2

for($x = 0; $x < count($array2); $x++){
        $array1[$x] = $array1[$x] . ' ' . $array2[$x];
    }