diff --git a/Sd1/swd1.xml b/Sd1/swd1.xml
index 3aad882f9c41d51269065aff11b6b97bc255d562..7340a24289acf6c668339774419a3f2805028222 100644
--- a/Sd1/swd1.xml
+++ b/Sd1/swd1.xml
@@ -454,8 +454,53 @@
               allows for setting the direction a wombat is going to move. Call
               it inserting different values by right clicking on a wombat
               instance. How do entered values relate to directions of a
-              wombat's movement? You may evaluate the result by actually
-              watching its moving direction. Is there another way?</para>
+              wombat's movement? Complete the following table by adding North,
+              South, East and West accordingly:</para>
+
+              <informaltable border="1" width="40%">
+                <colgroup width="45%"/>
+
+                <colgroup width="55%"/>
+
+                <tr>
+                  <th>Integer value</th>
+
+                  <th>Direction</th>
+                </tr>
+
+                <tr>
+                  <td>0</td>
+
+                  <td/>
+                </tr>
+
+                <tr>
+                  <td>1</td>
+
+                  <td/>
+                </tr>
+
+                <tr>
+                  <td>2</td>
+
+                  <td/>
+                </tr>
+
+                <tr>
+                  <td>3</td>
+
+                  <td/>
+                </tr>
+
+                <tr>
+                  <td>other</td>
+
+                  <td/>
+                </tr>
+              </informaltable>
+
+              <para>You may evaluate the result by actually watching its
+              moving direction. Is there another way?</para>
 
               <para>Hint: The <productname>Greenfoot</productname> framework
               allows you to inspect an object's internal attribute
@@ -519,6 +564,53 @@
             </answer>
           </qandaentry>
         </qandadiv>
+
+        <qandadiv>
+          <qandaentry>
+            <question>
+              <para>Representing directions by integer values ranging from 1
+              to 4 may be considered error prone. Explain possible
+              problems.</para>
+
+              <para>Hint: The <productname>Greenfoot</productname>
+              <filename>leaves-and-wombats</filename> scenario code contains
+              statements like <code>setDirection(EAST)</code>. But what about
+              <code>setDirection(35)</code> ?</para>
+            </question>
+
+            <answer>
+              <glosslist>
+                <para>A programmer may consistently use the predefined integer
+                values <code>EAST</code>, <code>WEST</code>,
+                <code>NORTH</code> and <code>SOUTH</code> but may use ordinary
+                integer values {0, 1, 2, 3} as well. This imposes the
+                following problems:</para>
+
+                <glossentry>
+                  <glossterm>Code Readability</glossterm>
+
+                  <glossdef>
+                    <para>A statement like <code>setDirection(2)</code> will
+                    be more difficult to understand than its counterpart
+                    <code>setDirection(NORTH)</code>. Currently we cannot
+                    enforce the second way of coding.</para>
+                  </glossdef>
+                </glossentry>
+
+                <glossentry>
+                  <glossterm>Possible programming errors</glossterm>
+
+                  <glossdef>
+                    <para>A programmer may be misled to use illegal
+                    directional values. Keeping a wrong set of directions in
+                    mind e.g {1, 2, 3, 4} rather than {0, 1, 2, 3} will result
+                    in errors. These may be hard to trace </para>
+                  </glossdef>
+                </glossentry>
+              </glosslist>
+            </answer>
+          </qandaentry>
+        </qandadiv>
       </qandaset>
     </section>