Ключевые слова: 20, 20th, appointment, background, birthday, business, calendar, computer, concept, conceptual, corporate, daily, date, day, deadline, december, design, diary, elearning, empty space, event, eyeglass, freelance, freelancer, idea, important, laptop, media, message, month, monthly, note, notice, number, office, organize, organizer, outsource, planner, remember, remind, reminder, selfeducation, sign, symbol, time, twentieth, twenty, winter, workplace,