Passengers who plan to go to Beijing and return to Beijing can normally go to Beijing and return to Beijing with the negative certificate of nucleic acid test within 48 hours and the green code of "Beijing Health Treasure" on the premise of normal temperature measurement and personal protection. It is recommended to conduct a nucleic acid test within 24 hours after arriving in Beijing, and conduct a nucleic acid test again within 24 hours and 72 hours after arriving in Beijing. No dinners, no parties, no places crowded within 7 days after arriving in Beijing.