diff --git a/language/operators.xml b/language/operators.xml
index 0b8f04c4e9..2b5f6c933e 100644
--- a/language/operators.xml
+++ b/language/operators.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="iso-8859-1"?>
-<!-- $Revision: 1.55 $ -->
+<!-- $Revision: 1.56 $ -->
  <chapter id="language.operators">
   <title>Operators</title>
   <simpara>
@@ -228,7 +228,11 @@
     <informalexample>
      <programlisting role="php"> 
 <![CDATA[
+<?php
+
 $a = ($b = 4) + 5; // $a is equal to 9 now, and $b has been set to 4.
+
+?>
 ]]>
      </programlisting>
     </informalexample>
@@ -242,10 +246,14 @@ $a = ($b = 4) + 5; // $a is equal to 9 now, and $b has been set to 4.
     <informalexample>
      <programlisting role="php">
 <![CDATA[
+<?php
+
 $a = 3;
 $a += 5; // sets $a to 8, as if we had said: $a = $a + 5;
 $b = "Hello ";
 $b .= "There!"; // sets $b to "Hello There!", just like $b = $b . "There!";
+
+?>
 ]]>
      </programlisting>
     </informalexample>
@@ -531,8 +539,10 @@ $value = @$cache[$key];
     <informalexample>
      <programlisting role="php">
 <![CDATA[
+<?php
 $output = `ls -al`;
 echo "<pre>$output</pre>";
+?>
 ]]>
      </programlisting>
     </informalexample>
@@ -725,11 +735,13 @@ AC
     <informalexample>
      <programlisting role="php">
 <![CDATA[
+<?php
 $a = "Hello ";
 $b = $a . "World!"; // now $b contains "Hello World!"
 
 $a = "Hello ";
 $a .= "World!";     // now $a contains "Hello World!"
+?>
 ]]>
      </programlisting>
     </informalexample>
@@ -752,12 +764,14 @@ $a .= "World!";     // now $a contains "Hello World!"
     <informalexample>
      <programlisting role="php">
 <![CDATA[
+<?php
 $a = array("a" => "apple", "b" => "banana");
 $b = array("a" =>"pear", "b" => "strawberry", "c" => "cherry");
 
 $c = $a + $b;
 
 var_dump($c);
+?>
 ]]>
      </programlisting>
     </informalexample>