--- a/mk	Tue Sep 26 12:03:24 2017 +0100
+++ b/mk	Tue Sep 26 12:10:41 2017 +0100
@@ -1,8 +1,9 @@
 #!/bin/sh
 set -e
 
+subdirs=${1:-"slides handouts hws coursework"} 
 #subdirs="slides handouts hws"
-subdirs="hws"
+#subdirs="hws"
 
 echo $subdirs
 
@@ -12,4 +13,4 @@
      xelatex $fl
   done
   cd ..
-done
\ No newline at end of file
+done