copy edits

Author: gmiller-mdb

source/reference/associations.txt

@@ -1211,9 +1211,10 @@ that a bundle may contain other bundles or products:
     has_many :items, polymorphic: true
   end
 
-Starting in version 9.0.2, Mongoid adds support to custom polymorphic types via
-a global registry. You can now specify alternative keys to represent different
-classes, thus decoupling the code from the data. For example:
+Starting in version 9.0.2, Mongoid adds support to custom polymorphic types through
+a global registry. You can specify alternative keys to represent different
+classes, thus decoupling the code from the data. The following example specifies
+the string ``"dept"`` as an alternate key for the ``Department`` class:
 
 .. code-block:: ruby
 
@@ -1223,16 +1224,18 @@ classes, thus decoupling the code from the data. For example:
     has_many :managers, as: :unit
   end
 
-The ``identify_as 'dept'`` directive says that this class should be identified by
-the string "dept" in the database. You can specify multiple aliases, too (e.g. 
-``entify_as 'dept', 'div', 'agency'``), in which case the first key is the "default",
-and the others are only used for looking up records. This lets you refactor your 
-code without breaking the associations in your data. 
+The ``identify_as 'dept'`` directive instructs Mongoid to store this class in the
+database as the string ``"dept"``. You can also specify multiple aliases. For 
+example, you can specify the option as: ``identify_as 'dept', 'div', 'agency'``,
+in which case the first key is the "default", and the others are used only for 
+looking up records. This lets you refactor your code without breaking the associations
+in your data. 
 
-Note that these aliases are global; the keys you specify must be unique across your
+These aliases are global. The keys you specify must be unique across your
 entire code base. However, it is possible to register alternative resolvers, which
 must be used for different subsets of your models. In this case, the keys must
-only be unique for each resolver. For example:
+only be unique for each resolver. The following example shows how to register
+alternate resolvers: 
 
 .. code-block:: ruby
 
@@ -1245,26 +1248,15 @@ only be unique for each resolver. For example:
       identify_as 'dept', resolver: :eng
     end
 
-    class Manager
-      include Mongoid::Document
-      belongs_to :unit, polymorphic: :eng
-    end
-  end
-
   module Purchasing
     class Department
       include Mongoid::Document
       identify_as 'dept', resolver: :purch
     end
 
-    class Manager
-      include Mongoid::Document
-      belongs_to :unit, polymorphic: :purch
-    end
-  end
 
 Both ``Engineering::Department`` and ``Purchasing::Department`` are aliased as 
-``"dept"``, but use their own resolver, so there is no conflict.
+``"dept"``, but use their own resolver to avoid conflicts. 
 
 ``has_and_belongs_to_many`` associations do not support polymorphism.