diff --git a/VL1/VL1_document_structure.tex b/VL1/VL1_document_structure.tex
index de2af15..9255e18 100644
--- a/VL1/VL1_document_structure.tex
+++ b/VL1/VL1_document_structure.tex
@@ -64,11 +64,15 @@
 
 \subsubsection{Pattern matching}
 
-\slide{./content/VL1_functions_and_control_structures2.tex}
+\slide{./content/VL1_pattern_matching.tex}
+
+\subsubsection{Case... of}
+
+\slide{./content/VL1_case_of.tex}
 
 \subsubsection{Guards and recursion}
 
-\slide{./content/VL1_functions_and_control_structures3.tex}
+\slide{./content/VL1_guards_and_recursion.tex}
 
 \subsection{Lists}
 
diff --git a/VL1/content/VL1_case_of.tex b/VL1/content/VL1_case_of.tex
new file mode 100644
index 0000000..bd2b361
--- /dev/null
+++ b/VL1/content/VL1_case_of.tex
@@ -0,0 +1,10 @@
+We can also pattern match on the result of a real expression, not just the input. For that, we write:
+
+\begin{haskellcode}
+f :: Int -> Bool
+f x = case x - 2 of
+  2 -> True
+  5 -> True
+  y -> False
+\end{haskellcode}
+This allows more powerful pattern matching, especially when we define our own data structures (not this lecture).
\ No newline at end of file
diff --git a/VL1/content/VL1_functions_and_control_structures3.tex b/VL1/content/VL1_guards_and_recursion.tex
similarity index 100%
rename from VL1/content/VL1_functions_and_control_structures3.tex
rename to VL1/content/VL1_guards_and_recursion.tex
diff --git a/VL1/content/VL1_functions_and_control_structures2.tex b/VL1/content/VL1_pattern_matching.tex
similarity index 100%
rename from VL1/content/VL1_functions_and_control_structures2.tex
rename to VL1/content/VL1_pattern_matching.tex