properly comment out php in html code example

Example 1: php comment

<?php
// This is a single-line comment

# This is also a single-line comment
  
/*
This is a multiple-lines comment block
that spans over multiple
lines
*/
  
// You can also use comments to leave out parts of a code line
$x = 5 /* + 15 */ + 5;
echo $x;
?>

Example 2: comments in php

//For a single line comment use //:
//this is a comment too
//for multi-line comments use /* and */:
/* <--start of multi-line comment
this is a comment

this is a comment too (end of multi-line comment)-->*/