@prefix md: <http://www.w3.org/ns/md#> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfa: <http://www.w3.org/ns/rdfa#> .
@prefix schema: <http://schema.org/> .

<sdo_eg_md_21.html> md:item (
 [ a schema:Article;
   schema:author "John Doe";
   schema:interactionCount "UserTweets:1203",
     "UserComments:78";
   schema:name "How to Tie a Reef Knot"]);
   rdfa:usesVocabulary schema: .