diff --git a/content/concepts/world_builder.md b/content/concepts/world_builder.md
index dba0250..b7e8bc6 100644
--- a/content/concepts/world_builder.md
+++ b/content/concepts/world_builder.md
@@ -6,7 +6,7 @@ weight: 35
 
 WorldBuilder is used to construct a World from Engines, Renderers, and an initial state of Entities, Components, and Messages.
 
-The WorldBuilder enforces certain rules about Engine structure. It is forbidden to have messages create cycles between Engines, and no Component may not be mutated by more than one Engine without declaring a priority.
+The WorldBuilder enforces certain rules about Engine structure. It is forbidden to have messages create cycles between Engines, and no Component may be mutated by more than one Engine without declaring a priority.
 
 The WorldBuilder uses Engines and their Message read/send information to determine a valid ordering of the Engines, which is given to the World.