You can't using PHP... u will have to use javascript.
If you insist on PHP, try thinking on the following lines:
You have to ensure that you define the areas correctly on the page you want to print, maybe using anchors.
At the end of each anchor, point to a different php file, say print.php. When print.php is accessed, it will fetch the file using fopen or whatever, look up the anchor, and the text that follows it till the next anchor, and display just that much text.
Get it?
ex.
<body>
<a name="para1"> </a>
This is para 1. This is para 1. This is para 1. This is para 1. This is para 1. This is para 1. This is para 1. This is para 1. This is para 1. This is para 1. This is para 1. This is para 1. This is para 1. This is para 1. This is para 1. <a href="print.php?para=para1">print above para</a>
<a name="para2"> </a>
This is para 2. This is para 2. This is para 2. This is para 2. This is para 2. This is para 2. This is para 2. This is para 2. This is para 2. This is para 2. This is para 2. This is para 2.
<a href="print.php?para=para2">print above para</a>
</body>
...
and in in print.php , do an fopen look for the anchor para1, till the next anchor, get the contents.
HTH
