Method of inserting newline characters in the middle of weaving php Chinese character string

The method of inserting a newline character in the middle of the weaving php Chinese character string
function strsub($str)
{ strcount = mbstrlen (str_count=mb_strlen(
$st{r}_{c}ount=m{b}_{s}trlen($str,‘utf-8’);
$mid=ceil($str_count/2);
return mb_substr($str,0,$mid,‘utf-8’)."
".mb_substr($str,$mid,$str_count,‘utf-8’);
}