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>
    <alllinks galcontinue="B-17轰炸机|543883" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1508" ns="0" title="日本" />
      <page pageid="16918" ns="0" title="西班牙语" />
      <page pageid="17251" ns="0" title="法语" />
      <page pageid="139959" ns="0" title="萨拉热窝" />
      <page pageid="377416" ns="0" title="法語" />
      <page pageid="451153" ns="0" title="无人航空载具" />
      <page pageid="483834" ns="0" title="美国陆军" />
      <page pageid="543570" ns="0" title="旗语" />
      <page pageid="543880" ns="0" title="美国陆军航空军" />
      <page pageid="543883" ns="0" title="美国空军" />
    </pages>
  </query>
</api>