(: use a modified identity function to restructure the original XML :)
declare function local:copy($element as element()) as element() {
   element {node-name($element)}
      {$element/@*,
        for $child in $element/node()
        return
              if (name($child) ="syllabus")
               (: syllabus is a summary of the question bank and hence redundant :)
              then ()  
              else 
              if (name($child) = "title")
              then 
               if (name($child/..) = "subelement")  
               (: get the title prefix and promote the id part to an attribute of the enclosing element - fortuitously the previous element. Trim the title
                  e.g. T1B - Authorized frequencies; frequency allocations, ITU regions, emission type, restricted sub-bands, spectrum sharing, transmissions near band edges
               :)
               then 
                       (attribute id {substring-before(substring-after($child,"SUBELEMENT ")," -")},
                       element title {substring-after ($child," - ")}
                       )
               else
               if (name($child/..) = "group")
               (: simialrly fo rthe group title
               e.g. T1B - Authorized frequencies; frequency allocations, ITU regions, emission type, restricted sub-bands, spectrum sharing, transmissions near band edges 
               :)
               then 
                        (attribute id {substring-before($child," -")},
                         element title {substring-after ($child," - ")}
                       )
                else
                       $child
               else
                if (name($child) = "number")
                (:  promote question number to the id of the question  :)
                then 
                        attribute id {$child}
                else
                if ($child instance of element())
                (: recurse on any other element :)
                 then local:copy($child)
                 else $child
      }
};
let $doc1 := doc("/db/Wiki/Ham/Element2-2010.xml")/pool

return local:copy($doc1)