<script src="http://code.jquery.com/jquery-1.7.2.min.js"></script>
<script type="text/javascript">
$(document).ready(
function()
{
$("#link").click(
function()
{
$("#more").toggle("slow");
});
});
</script>
<div>
<p>Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Pellentesque metus eros, rutrum at, hendrerit nec, posuere ac.<a href="#" id="link">więcej</a></p>
<p id="more" style="display: none;">Vivamus pretium fringilla metus. Praesent a enim eu metus scelerisque tincidunt. In auctor lorem et leo.</p>
</div>