6: 00 to 8: 00 a. m. According to the query of Careers. com, the promotion crowd in Nurse is suitable for Ma Bao or expectant mothers. One day is limited, and they need to take care of their babies. The promotion time should be chosen at the right stage. 6:00-8:00 am belongs to the free stage in Ma Bao, which can be used as the promotion time for nurses.