diff --git a/_includes/sqlstyle.guide.zh.md b/_includes/sqlstyle.guide.zh.md
index 7421d39..bc653a2 100644
--- a/_includes/sqlstyle.guide.zh.md
+++ b/_includes/sqlstyle.guide.zh.md
@@ -86,8 +86,8 @@ SELECT first_name
 ```sql
 SELECT first_name AS fn
   FROM staff AS s1
-  JOIN students AS s2
-    ON s2.mentor_id = s1.staff_num;
+       JOIN students AS s2
+       ON s2.mentor_id = s1.staff_num;
 ```
 ```sql
 SELECT SUM(s.monitor_tally) AS monitor_total