A blackboard with greeting words on it is seen in a high school in Rome, Italy, Sept. 13, 2021. Students in Italy started to return to schools on Monday. Teachers and staff in Italy's schools and universities are obliged to have the COVID-19 Green Pass. (Photo by Alberto Lingria/Xinhua)
Students show their "Green Passes" in a high school in Rome, Italy, Sept. 13, 2021. Students in Italy started to return to schools on Monday. Teachers and staff in Italy's schools and universities are obliged to have the COVID-19 Green Pass. (Photo by Alberto Lingria/Xinhua)
Students attend a class in a high school in Rome, Italy, Sept. 13, 2021. Students in Italy started to return to schools on Monday. Teachers and staff in Italy's schools and universities are obliged to have the COVID-19 Green Pass. (Photo by Alberto Lingria/Xinhua)
Students wait to enter a high school in Rome, Italy, Sept. 13, 2021. Students in Italy started to return to schools on Monday. Teachers and staff in Italy's schools and universities are obliged to have the COVID-19 Green Pass. (Photo by Alberto Lingria/Xinhua)
A staff member checks the "Green Pass" of a high school teacher in Rome, Italy, Sept. 13, 2021. Students in Italy started to return to schools on Monday. Teachers and staff in Italy's schools and universities are obliged to have the COVID-19 Green Pass. (Photo by Alberto Lingria/Xinhua)
