I think this is what you are looking for...content.txt:
<?php //Poem 1...if ($_GET["poem"]=="1"){ echo "roses are red"; exit();}//Poem 2 and on...elseif ($_GET["poem"]=="2"){ echo "violets are blue"; exit();}elseif ($_GET["poem"]=="3"){ echo "sugar is sweet"; exit();}elseif ($_GET["poem"]=="4"){ echo "and so are you"; exit();}//IF NO POEM IS SELECTEDelse {echo "No poem selected"; exit();};?>
..and so on and so on. If you need to use quotes in your poem you need to cancel the out with \" like this:
elseif ($_GET["poem"]=="5"){ echo "she said \"I love you\" and got on the train"; exit();}
The exit(); is in there so once the correct poem is retrieved, the rest of the script isnt parsed.Now, include the above script in your page with the following code
<?php include("http://www.yourdomain.com/content.txt"); ?>
Be sure to change yourdomain.com to your actual domain.And remember, to call a specific poem, make sure the url called is http://www.yourdomain.com/index.php?poem=2 and poem 2 will be inserted into that page.