Outputting multiple content fields all wrapped in a div
Multiple ways to achieve this.


By creating a node tpl file for that particular content type.
By creating view.
But i think the best and easiest way is creating group in manage display. Check field group module.


Procedure to create group.


Go to structure->content types->content(ex-blog)->manage displays.
Add a new group of div type.
Drag the required field like field2 , field3 etc under it.


Print in tpl file.

It will be easy to find out if you will update the code snippet of node--case-study.tpl.php file. 

I think you need to first check by printing

echo '&lt;pre&gt;';
print_r($content);


and use this for 

&lt;div class="y"&gt;
  &lt;?php print($content['field1']); ?&gt;
&lt;/div&gt;

&lt;div class="x"&gt;
 &lt;?php 
    print($content['field2']);
    print($content['field3']);
    print($content['field4']); 
 ?&gt;
&lt;/div&gt;