diff --git a/lib/microformats2.rb b/lib/microformats2.rb
index a9968fc..cb906d0 100644
--- a/lib/microformats2.rb
+++ b/lib/microformats2.rb
@@ -1,6 +1,8 @@
 require "nokogiri"
 require "open-uri"
 require "json"
+require "active_support/inflector"
+
 require "microformats2/version"
 require "microformats2/format_parser"
 require "microformats2/property_parser"
diff --git a/lib/microformats2/format.rb b/lib/microformats2/format.rb
index ca443d6..65bd24e 100644
--- a/lib/microformats2/format.rb
+++ b/lib/microformats2/format.rb
@@ -82,13 +82,19 @@ module Microformats2
       unless respond_to?(mn)
         self.class.class_eval { attr_accessor mn }
       end
+      unless respond_to?(mn.pluralize)
+        self.class.class_eval { attr_accessor mn.pluralize }
+      end
     end
 
     def set_value(mn, value)
-      if current = send(mn)
+      unless current = send(mn)
+        send("#{mn}=", value)
+      end
+      if current = send(mn.pluralize)
         current << value
       else
-        send("#{mn}=", [value])
+        send("#{mn.pluralize}=", [value])
       end
     end
   end