diff --git a/index.bs b/index.bs
index db284731..b1cdd0a2 100644
--- a/index.bs
+++ b/index.bs
@@ -2800,7 +2800,7 @@ Appeal by Advisory Committee Representatives</h3>
 	and “Abstain”,
 	together with Comments.
 
-	The level of support needed for a [=Advisory Committee Override=] to pass
+	The level of support needed for an [=Advisory Committee Override=] to pass
 	depends on the level of participation by [=Advisory Committee Representatives=],
 	(including those who cast an explicit “abstain” ballot):
 	* if fewer than 5% participate,