add comment to echo php 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: php comment

// I'm a single, line comment 
#  I am another single line comments using #
/*
 And I am a 
 multiline comment
*/