diff --git a/book/syntax_exercises/012.md b/book/syntax_exercises/012.md
index f64f920..6f80704 100644
--- a/book/syntax_exercises/012.md
+++ b/book/syntax_exercises/012.md
@@ -161,7 +161,7 @@ sphinx-named-colors
 
 **Step B: Enable in `_config.yml`**
 
-In your `_config.yml` file (in the `book/` subdirectory of your repository), add the extension to the list of Sphinx extra extensions so that it's included in the building of your book:
+In your `_config.yml` file (in the `book/` subdirectory of your repository), ensure that the extension is added to the list of Sphinx extra extensions so that it's included in the building of your book:
 
 ```md
 sphinx: