diff --git a/koans/about_methods.rb b/koans/about_methods.rb
index fde97e9..d36e9ab 100644
--- a/koans/about_methods.rb
+++ b/koans/about_methods.rb
@@ -36,12 +36,12 @@ class AboutMethods < EdgeCase::Koan
     exception = assert_raise(___) do
       my_global_method
     end
-    assert_match(/#{__ of arguments")}/, exception.message)
+    assert_match(/__/, exception.message)
 
     exception = assert_raise(___) do
       my_global_method(1,2,3)
     end
-    assert_match(/#{__ of arguments")}/, exception.message)
+    assert_match(/__/, exception.message)
   end
 
   # ------------------------------------------------------------------
diff --git a/src/about_methods.rb b/src/about_methods.rb
index 78ed5b6..1497f9b 100644
--- a/src/about_methods.rb
+++ b/src/about_methods.rb
@@ -43,12 +43,15 @@ class AboutMethods < EdgeCase::Koan
     exception = assert_raise(___(ArgumentError)) do
       my_global_method
     end
-    assert_match(/#{__("wrong (number|#) of arguments")}/, exception.message)
+    #--
+    pattern = "wrong (number|#) of arguments"
+    #++
+    assert_match(/#{__(pattern)}/, exception.message)
 
     exception = assert_raise(___(ArgumentError)) do
       my_global_method(1,2,3)
     end
-    assert_match(/#{__("wrong (number|#) of arguments")}/, exception.message)
+    assert_match(/#{__(pattern)}/, exception.message)
   end
 
   # ------------------------------------------------------------------