diff --git a/docs/usage/index.md b/docs/usage/index.md
index daa2444..45e6b9c 100644
--- a/docs/usage/index.md
+++ b/docs/usage/index.md
@@ -13,7 +13,7 @@ The `exec` option will be true for every possible value
 except `0`, `no`, `off` and `false` (case insensitive).
 
 To enable automatic execution of code blocks for specific languages
-(without having to add the `exec="on" option to your code blocks),
+(without having to add the `exec="on"` option to your code blocks),
 set the `MARKDOWN_EXEC_AUTO` environment variable:
 
 ```bash