Drupal 7 : How to break title of content into multiple lines
As I understand you want have your nodes titled using pattern &lt;English name&gt;&lt;Arabic name&gt;, and split your title on 'language border' to different lines. As was mentioned node title is used in both places content title, and page title. 

So you can use changed pattern &lt;English name&gt;|&lt;Arabic name&gt; and override your template file in your theme. You can use str_replace before displaying title for your node. Also your page title will look ok, without changing theme more; and this solution support titles without | delimiter, or with more then 1.