diff -u b/core/lib/Drupal/Core/Extension/module.api.php b/core/lib/Drupal/Core/Extension/module.api.php
--- b/core/lib/Drupal/Core/Extension/module.api.php
+++ b/core/lib/Drupal/Core/Extension/module.api.php
@@ -501,8 +501,8 @@
  * which users will see when they run the update.php script.
  *
  * @section sec_notes Notes about the function body
- * Writing hook_update_N() functions is tricky. There are several reasons
- * why this is the case:
+ * Writing hook_update_N() functions is tricky. There are several reasons why
+ * this is the case:
  * - You do not know when updates will be run: someone could be keeping up with
  *   every update and run them when the database and code are in the same state
  *   as when you wrote your update function, or they could have waited until a
diff -u b/core/modules/system/src/Tests/Update/UpdatePathTestBase.php b/core/modules/system/src/Tests/Update/UpdatePathTestBase.php
--- b/core/modules/system/src/Tests/Update/UpdatePathTestBase.php
+++ b/core/modules/system/src/Tests/Update/UpdatePathTestBase.php
@@ -19,16 +19,15 @@
  *
  * To write an update test:
  * - Write the hook_update_N() implementations that you are testing.
- * - Create one or more database dump files, which will set the database
- *   to the "before updates" state. Normally, these will add some
- *   configuration data to the database, set up some tables/fields, etc.
+ * - Create one or more database dump files, which will set the database to the
+ *   "before updates" state. Normally, these will add some configuration data to
+ *   the database, set up some tables/fields, etc.
  * - Create a class that extends this class.
- * - In your setUp() method, point the $this->databaseDumpFiles variable
- *   to the database dump files, and then call parent::setUp() to run the
- *   base setUp() method in this class.
- * - In your test method, call $this->runUpdates() to run the necessary
- *   updates, and then use test assertions to verify that the result is what
- *   you expect.
+ * - In your setUp() method, point the $this->databaseDumpFiles variable to the
+ *   database dump files, and then call parent::setUp() to run the base setUp()
+ *   method in this class.
+ * - In your test method, call $this->runUpdates() to run the necessary updates,
+ *   and then use test assertions to verify that the result is what you expect.
  *
  * @ingroup update_api
  *