diff --git a/CppCoreGuidelines.md b/CppCoreGuidelines.md
index f547b5f..ea2d1e3 100644
--- a/CppCoreGuidelines.md
+++ b/CppCoreGuidelines.md
@@ -7204,7 +7204,7 @@ There are now two hierarchies:
 * interface: Smiley -> Circle -> Shape
 * implementation: Impl::Smiley -> Impl::Circle -> Impl::Shape
 
-Since each implementation derived from its interface as well as its implementation base class we get a lattice (DAG):
+Since each implementation is derived from its interface as well as its implementation base class we get a lattice (DAG):
 
     Smiley     ->         Circle     ->  Shape
       ^                     ^               ^