<code> <h1> </code>

<?
$data = "The cat likes to sit on the fence. He also likes to climb the tree.";

$find ="/the/";
$replace ="a";

//1. replace single word
Echo "$data <br>";
Echo preg_replace ($find, $replace, $data);

//create arrays
$find2 = array ('/the/', '/cat/');
$replace2 = array ('a', 'dog');

//2. replace with array values
Echo preg_replace ($find2, $replace2, $data);

//3. Replace just once
Echo preg_replace ($find2, $replace2, $data, 1);

//4. Keep a count of replacements
$count = 0;
Echo preg_replace ($find2, $replace2, $data, -1, $count);
Echo "<br>You have made $count replacements";

?>