--- a/slides/slides01.tex	Thu Apr 18 14:16:31 2019 +0100
+++ b/slides/slides01.tex	Wed Jul 17 11:17:52 2019 +0100
@@ -22,6 +22,9 @@
 
 
 
+
+
+
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \begin{frame}[t]
 \frametitle{%  
@@ -261,7 +264,7 @@
 lexer output: a sequence of tokens\smallskip\\
 \hspace{5mm}\code{key(read) lpar id(n) rpar semi}
 \end{bubble}
-\end{textblock}}
+\end{textblock}} 
 
 \only<3,4>{
 \begin{textblock}{1}(6,7.8)