diff -u b/core/lib/Drupal/Core/Config/Entity/ConfigEntityInterface.php b/core/lib/Drupal/Core/Config/Entity/ConfigEntityInterface.php
--- b/core/lib/Drupal/Core/Config/Entity/ConfigEntityInterface.php
+++ b/core/lib/Drupal/Core/Config/Entity/ConfigEntityInterface.php
@@ -18,7 +18,7 @@
    * Returns the original ID.
    *
    * @return string|null
-   *   The original ID or NULL.
+   *   The original ID, or NULL if no ID was set.
    */
   public function getOriginalId();
 
@@ -82,7 +82,7 @@
   public function status();
 
   /**
-   * Returns if this entity is changed as part of an import process.
+   * Returns if this entity is being changed as part of an import process.
    *
    * Code that makes persistent changes to new, changed, or deleted
    * configuration entities, but not imported entities that may already contain
@@ -90,12 +90,12 @@
    *
    * An example is \Drupal\node\Entity\NodeType::postSave(), which adds the
    * default body field to newly created node types. Imported entities already
-   * contain this field from when they were originally created, and should not
+   * contain this field from when they were originally created, and must not
    * get it again.
    *
    * @return bool
-   *   TRUE if the configuration entity is created, updated or deleted through
-   *   the import process.
+   *   TRUE if the configuration entity is being created, updated or deleted
+   *   through the import process.
    */
   public function isSyncing();