rules.rst: item class → item instance

docs/page-objects/rules.rst

@@ -10,9 +10,9 @@ URL and the requested output class (a :ref:`page object class
 <page-object-classes>` or an :ref:`item class <items>`).
 
 Rules are necessary if you want to request an item instance, because rules tell
-web-poet which page object class to use to generate your item class. Rules can
-also be useful as documentation or to get information about page object classes
-programmatically.
+web-poet which page object class to use to generate your item instance. Rules
+can also be useful as documentation or to get information about page object
+classes programmatically.
 
 :ref:`Rule precedence <rule-precedence>` can also be useful. For example, to
 implement generic page object classes that you can override for specific