--- a/cws/disclaimer.sty	Fri Aug 16 08:45:21 2019 +0100
+++ b/cws/disclaimer.sty	Tue Oct 29 09:54:52 2019 +0000
@@ -21,7 +21,8 @@
 \texttt{Array}s or \texttt{ListBuffer}s, for example. 
 
 \item Do not use \texttt{return} in your code! It has a different
-  meaning in Scala than in Java.
+  meaning in Scala than in Java. It changes the meaning of your program,
+  and you should never use it.
 
 \item Do not use \texttt{var}! This declares a mutable variable. Only
   use \texttt{val}!