You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information.
<?xml version="1.0"?>
<api>
  <query-continue>
    <allfileusages gafcontinue="C919大型客机首架机总装下线,2015年11月2日.jpg|374373" />
  </query-continue>
  <query>
    <pages>
      <page pageid="374373" ns="0" title="C919大型客机全纪录" />
      <page pageid="444085" ns="0" title="百年大計蒙特梭利專欄—教育為先 談幼小銜接(上)" />
    </pages>
  </query>
</api>