如何在PHP中从数组元素中拆分字符串？

I want to split array element's string. I have to split it at the fifth character, but if it's in the middle of the word, split it at the nearest whitespace. Like this:

// I have array like these
$array={"How are you ?","I am fine."};

//I want output like if we take length = 5.

$array1 = {"How are","you ?","I am fine."};  // array1[0] =how a   should be    array1[0] = how are  .

Look for nearest whitespace to the fifth character. Then return the first part from 0 until that character and put it into new array. Then put the second chunk (the one until the end) into the same array.

foreach ($array as $val) {
    $strpos = strpos($val, " ", 5);
    $array1[] = substr($val, 0, $strpos);
    $array1[] = substr($val, $strpos+1, strlen($val));
}