--- a/rdf-primer/index.html	Thu Nov 28 01:07:53 2013 +0100
+++ b/rdf-primer/index.html	Thu Nov 28 12:35:43 2013 +0100
@@ -190,8 +190,8 @@
 	  <li>RDFa [[!RDFA-PRIMER]] (for HTML embedding)</li>
 	  <li>N-Triples and N-Quads (line-based exchange formats)</li>
 	</ul></li> 
-      <li>The RDF Vocabulary Description Language RDF Schema
-      [[!RDF-SCHEMA]]</li>
+      <li>A document describing RDF Schema [[!RDF-SCHEMA]], which
+    provides a data-modeling vocabulary for RDF data. </li>
     </ul>
 
     <!--
@@ -496,18 +496,18 @@
     </tr>
     <tr>
       <td><em>Class</em> (a class)</td>
-      <td><code>rdfs:Class</code></td>
-      <td>class of RDF classes</td>
+      <td><code><strong>s</strong> rdf:type rdfs:Class</code></td>
+      <td><strong>s</strong> (a resource) is an RDF class</td>
     </tr>
     <tr>
       <td><em>Property</em> (a class)</td>
-      <td><code>rdf:Property</code></td>
-      <td>class of RDF properties</td>
+      <td><code><strong>p</strong> rdf:type rdf:Property</code></td>
+      <td><strong>p</strong> (a resource) is an RDF property</td>
     </tr>
     <tr>
       <td><em>type</em> (a property)</td>
       <td><strong>s</strong> <code>rdf:type</code> <striong>o</strong></td>
-      <td><strong>s</strong> (any resource) is an instance of <striong>o</strong> (a class)</td>
+      <td><strong>s</strong> (a resource) is an instance of <striong>o</strong> (a class)</td>
     </tr>
     <tr>
       <td><em>subClassOf</em> (a property)</td>
@@ -540,7 +540,7 @@
 historical artefact, which is preserved for backward
 compatibility.</p>
 
-<p>With the help of RDF Schema one can build a semantic model of RDF data. A simple
+<p>With the help of RDF Schema one can build a model of RDF data. A simple
 example:</p>
 
   <pre class="example" id="rdfs-example">
@@ -670,11 +670,19 @@
 </pre>
 
 <p>Lines 1-6 contain a number of directives which provide shorthands for
-writing down IRIs. A URI like <code>http://xmlns.com/foaf/0.1/</code>
-is colloquially called a namespace URI, in this case of the FOAF
-vocabulary. The "base" prefix is used if no prefix is provided 
-(see <code>bob#me</code> on line 8). A period is used to signal the end
-of a Turtle statement. </p>
+writing down IRIs. In Turtle IRIs are enclosed in angle brackets
+(<code><></code>). Relative IRIs (such as <code>bob#me</code> on line 8) are 
+resolved agains a base IRI, specified here in line 1.
+Lines 2-6 define IRI prefixes (such as <code>foaf:</code>), which  can
+be use for prefixed names (such as <code>foaf:Person</code>) instead of full IRIs.
+The corresponding IRI is constructed by replacing the prefix with its
+corresponding IRI (in this example, <code>foaf:Person</code> stands for
+<code><http://xmlns.com/foaf/0.1/Person></code>). A period is used to
+signal the end of a Turtle statement. </p>
+
+<p class="issue">
+Use SPARQL-style prefix?
+</p>
 
 <p>Lines 8-12 show how Turtle provides a shorthand for a set of
 triples with the same subject. Lines 9-12 specify the predicate-object
@@ -687,11 +695,12 @@
 <code>&lt;http://example.org/bob#me&gt; &lt;http://xmlns.com/foaf/0.1/knows&gt; &lt;http://example.org/alice#me&gt; .</code>
 </pre>
 
-<p>Line 9 shows an example of a special kind of syntactic sugar. The
+<p>Line 9 shows an example of a special kind of syntactic sugar. The triple
+should informally be read as "Bob (is) a Person". The
 <code>a</code> predicate 
 is a shorthand for the property <code>rdf:type</code> which models the
 instance relation (see Table <a href="#table-rdf-schema">"RDF Schema
-constructs"</a>). The <code>a</code> shorthand is intended to match the human
+constructs"</a>). The <code> a</code> shorthand is intended to match the human
 intuition about <code>rdf:type</code>. <p>
 
 <p>In line 11 we see an example of a literal, in this case a date. The
@@ -700,19 +709,18 @@
 <a href="http://www.w3.org/TR/xmlschema11-2/#date">date</a>.</p>
 
 <p>Because string literals are so ubiquitous Turtle allows the user to
-omit the datatype when writing a string literal. Thus, <code>"This is a
-string"</code> is equivalent to <code>"This is a
-string"^^xsd:string</code>. </p>
+omit the datatype when writing a string literal. Thus, <code>"Leonardo
+da Vinci"</code> in line 16 is equivalent to <code>"Leonardo da Vinci"^^xsd:string</code>. </p>
 
 <p>In case of language-tagged strings the tag
 appears directly after the string, separated by a <code>@</code>
-symbol, e.g. <code>"Leonardo da Vinci"@it</code>. The
-datatype of language-tagged strings is not specifed explictly
-in Turtle. </p>
+symbol, e.g. <code>"Leonard de Vinci"@fr</code>.</p>
 
 <p class="note">For technical reasons the datatype of language-tagged
 strings is not <code>xsd:string</code> but
-<code>rdf:langString</code>.</p>
+<code>rdf:langString</code>. The
+datatype of language-tagged strings is never specifed explictly
+in Turtle.</p>
 
 <p>The above is by no means a full account of the Turtle syntax. For
 more details about the syntax of Turtle the reader is referred to the
@@ -835,9 +843,8 @@
       <dt>RDF/XML</dt>
       <dd>RDF/XML [[RDF-SYNTAX-GRAMMAR]] (<a href="#subsection-rdf-xml">example</a>)
       provides an XML syntax for RDF
-      graphs. RDF/XML was the only normative syntax for RDF before the
-      RDF 1.1 set of recommendations introduced multiple 
-      syntaxes for RDF graphs. </dd>
+      graphs. RDF/XML was the only normative syntax for RDF when RDF
+      1.0 was published in 2004. </dd>
    </dl>
 
    <p>For more information about these syntaxes consult the references.</p>
@@ -901,6 +908,9 @@
    <code>ex:Marriage rdf:type rdfs:Class . </code>
    </pre>
 
+<p class="issue">Consider replacing the example above with an example
+where a resource is both a class and an instance.</p>
+
    <p>The examples in this section are just meant to give the reader
 some feeling about what the RDF Semantics brings you. Please consult
 [[RDF11-MT]] for a complete description.</p>