Unscheduled work system refers to a system of working hours adopted by employees of enterprises that cannot be measured according to standard working hours or require manual work due to production characteristics, work characteristics, or the scope of their responsibilities. According to the above definitions, Which of the following are irregular working hours (). ['Wang teaches in a key middle school in a city and often corrects his homework overtime.', 'Li is a reporter for a newspaper and often reports on-site news.', 'Zhang as a brand promoter in a large supermarket.', 'Zhao is receiving work in the logistics department of a city government.']