diff --git a/reference/classobj/functions/class-alias.xml b/reference/classobj/functions/class-alias.xml
index 2dffccdc79..ead4533dbb 100644
--- a/reference/classobj/functions/class-alias.xml
+++ b/reference/classobj/functions/class-alias.xml
@@ -14,7 +14,7 @@
   </methodsynopsis>
   <para>
    Creates an alias named <parameter>alias</parameter>
-   base on the defined class <parameter>original</parameter>.
+   based on the defined class <parameter>original</parameter>.
    The aliased class is exactly the same as the original class.
   </para>
  </refsect1>