JSFiddle - React, Tailwind, and code Playground
HTML
<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.4/themes/ui-lightness/jquery-ui.css">
<ul class="wrapper">
<li><a href="#"><img src="#" /></a></li>
<li><a href="#"><img src="#" /></a></li>
<li><a href="#"><img src="#" /></a></li>
<li><a href="#"><img src="#" /></a></li>
<li><a href="#"><img src="#" /></a></li>
<li><a href="#"><img src="#" /></a></li>
<li><a href="#"><img src="#" /></a></li>
<li><a href="#"><img src="#" /></a></li>
</ul>
CSS
.recommend{
border: 2px dashed orange;
margin: 4px;
}
JavaScript
var a = $('ul.wrapper > li');
for( var i = 0; i < a.length; i+=3 ) {
a.slice(i, i+3).wrapAll('<div class="recommend"></div>');
}