array( 'access', 'advice', 'art', 'baggage', 'dances', 'equipment', 'fish', 'fuel', 'furniture', 'food', 'heat', 'honey', 'homework', 'impatience', 'information', 'knowledge', 'luggage', 'money', 'music', 'news', 'patience', 'progress', 'pollution', 'research', 'rice', 'sand', 'series', 'sheep', 'sms', 'species', 'staff', 'toothpaste', 'traffic', 'understanding', 'water', 'weather', 'work', ), 'irregular' => array( 'child' => 'children', 'clothes' => 'clothing', 'man' => 'men', 'movie' => 'movies', 'person' => 'people', 'woman' => 'women', 'mouse' => 'mice', 'goose' => 'geese', 'ox' => 'oxen', 'leaf' => 'leaves', 'course' => 'courses', 'size' => 'sizes', ), );