--- a/ProgTutorial/Intro.thy	Thu Mar 19 23:21:26 2009 +0100
+++ b/ProgTutorial/Intro.thy	Sat Mar 21 12:35:03 2009 +0100
@@ -151,7 +151,7 @@
 
   {\Large\bf
   This document is still in the process of being written! All of the
-  text is still under constructions. Sections and 
+  text is still under construction. Sections and 
   chapters that are under \underline{heavy} construction are marked 
   with TBD.}