diff --git a/about/format.html b/about/format.html
index e916a6c..fc76777 100644
--- a/about/format.html
+++ b/about/format.html
@@ -2,7 +2,7 @@
-Book structure
+Book structure need to improve
At the top level, books are listed by language: en, ru ...
Each language is a separate book.