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>
    <alltransclusions gatcontinue="鄭鴻文_書法家_書法藝術上版型01|23" />
  </query-continue>
  <query>
    <pages>
      <page pageid="2" ns="0" title="首頁" />
      <page pageid="11" ns="0" title="鄭鴻文 書法情報" />
      <page pageid="12" ns="0" title="鄭鴻文 詩文" />
      <page pageid="22" ns="0" title="鄭鴻文 生活網誌" />
      <page pageid="27" ns="10" title="模板:鄭鴻文 書法藝術 書法情報" />
      <page pageid="206" ns="0" title="02" />
      <page pageid="385" ns="0" title="Q版:鴻文" />
      <page pageid="742" ns="0" title="2" />
    </pages>
  </query>
</api>