XML element won't let me add text as well as attributes

Following code adds and save new element to my XML file, the problem is, that I'm not sure how to insert text, as well as the attributes.

How to do this properly?

        XmlNode lang = xmlDoc.GetElementsByTagName("languages").Item(0);
        XmlElement lang_element = (XmlElement)lang;
        XmlDocument doc_lang = lang_element.OwnerDocument;
        XmlElement lang_new_element = doc_lang.CreateElement("language");
        lang_new_element.SetAttribute("id", (CountLanguages() + 1).ToString());
        lang_element.AppendChild(lang_new_element);
        xmlDoc.Save("..\\..\\..\\new_xml.xml");

This is how my XML should look.

  <languages>
    <language id="0">NULL</language>
  </languages>