Approval.

uk/day_of_week.php

@@ -1,11 +1,11 @@
 <?PHP
 declare(strict_types = 1);
 $day_of_week = array (
-  'monday' => 'Monday',
-  'tuesday' => 'Tuesday',
-  'wednesday' => 'Wednesday',
-  'thursday' => 'Thursday',
-  'friday' => 'Friday',
-  'saturday' => 'Saturday',
-  'sunday' => 'Sunday',
+  'monday' => 'Понеділок',
+  'tuesday' => 'Вівторок',
+  'wednesday' => 'Середа',
+  'thursday' => 'Четвер',
+  'friday' => 'П’ятниця',
+  'saturday' => 'Субота',
+  'sunday' => 'Неділя',
 );