diff --git a/book/service_container.rst b/book/service_container.rst
index 14d03bb0402..c313fda3ba7 100644
--- a/book/service_container.rst
+++ b/book/service_container.rst
@@ -848,8 +848,8 @@ the framework.
 
 .. tip::
 
-    Be sure that ``swiftmailer`` entry appears in your application
-    configuration. As you mentioned in :ref:`service-container-extension-configuration`,
+    Be sure that the ``swiftmailer`` entry appears in your application
+    configuration. As was mentioned in :ref:`service-container-extension-configuration`,
     the ``swiftmailer`` key invokes the service extension from the
     ``SwiftmailerBundle``, which registers the ``mailer`` service.