Ключевые слова: 15, 15th, 2017, 2018, 2019, appointment, background, birthday, blue, business, calendar, concept, conceptual, cork, corporate, daily, date, day, deadline, december, design, diary, empty space, event, february, fifteen, fifteenth, idea, important, message, month, monthly, note, notepad, notice, notice board, number, organize, organizer, planner, remember, remind, reminder, sign, tax, time, timeframe, tomorrow, winter, workplace,