diff --git a/rdf/RDF.ipynb b/rdf/RDF.ipynb
index 1688415..e4917af 100644
--- a/rdf/RDF.ipynb
+++ b/rdf/RDF.ipynb
@@ -89,7 +89,18 @@
   },
   {
    "cell_type": "markdown",
-   "metadata": {},
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "checksum": "5c2cccdf6463262a0f8bc89c64f97fb2",
+     "grade": false,
+     "grade_id": "cell-d8db3c16cee92ac1",
+     "locked": true,
+     "schema_version": 1,
+     "solution": false
+    }
+   },
    "source": [
     "# Linked Data, RDF and Turtle\n",
     "\n",
@@ -167,7 +178,18 @@
   },
   {
    "cell_type": "markdown",
-   "metadata": {},
+   "metadata": {
+    "deletable": false,
+    "editable": false,
+    "nbgrader": {
+     "checksum": "d2849a6154d4807b405e6ec84601c231",
+     "grade": false,
+     "grade_id": "cell-14e2327285737802",
+     "locked": true,
+     "schema_version": 1,
+     "solution": false
+    }
+   },
    "source": [
     "# Vocabularies and schema.org\n",
     "\n",
@@ -303,18 +325,38 @@
    "cell_type": "markdown",
    "metadata": {
     "deletable": false,
+    "editable": false,
     "nbgrader": {
-     "checksum": "d2a1ff53084a9bd94110f071a67d9305",
-     "grade": true,
+     "checksum": "61933311e76dd200b63032f42f26b11d",
+     "grade": false,
      "grade_id": "cell-da88c2f8170436fe",
-     "locked": false,
-     "points": 0,
+     "locked": true,
      "schema_version": 1,
-     "solution": true
+     "solution": false
     }
    },
    "source": [
-    "# YOUR ANSWER HERE"
+    "Turtle is usually written in standalone files (e.g. `mydefinition.ttl`).\n",
+    "To write Turtle definitions inside our notebook, and to make it easy to test them, we will use a special magic command: `%%ttl`.\n",
+    "\n",
+    "To make sure everything works, let's try first with an example.\n",
+    "\n",
+    "\n",
+    "Copy/paste this solution below:\n",
+    "\n",
+    "```turtle\n",
+    "@prefix foaf: <http://xmlns.com/foaf/0.1/> .\n",
+    "@prefix geo: <http://www.w3.org/2003/01/geo/wgs84_pos#> .\n",
+    "@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .\n",
+    "\n",
+    "<http://purl.org/net/bsletten> \n",
+    "    a foaf:Person;\n",
+    "    foaf:interest <http://www.w3.org/2000/01/sw/>;\n",
+    "    foaf:based_near [\n",
+    "        geo:lat \"34.0736111\" ;\n",
+    "        geo:lon \"-118.3994444\"\n",
+    "   ] .\n",
+    "```"
    ]
   },
   {