[Department of Pediatrics] in recent years, the myopia rate of teenagers in the world has remained high. Since the COVID-19 epidemic, due to the reduction of outdoor activities and the increase of online class time using electronic equipment, the myopia rate of adolescents has further increased. In order to help teenagers prevent myopia and grow up healthily, ophthalmologists from many countries have put forward scientific suggestions on eye use. The first trick of scientific eye use: ensure correct posture. The Japanese ophthalmologists Association recommends that to prevent myopia, we should pay attention to the correct posture when reading and writing, sit upright, and ensure that the distance between eyes and books is about 30cm. The Korean Times quoted Kim Ying soo, a doctor at Kim's eye hospital in South Korea, as saying that under the remote teaching mode, students should learn how to correctly use electronic equipment, such as at least 50 cm from the screen. The second trick of using eyes scientifically: avoid eye fatigue. The Japanese Association of ophthalmologists recommends that in order to prevent eye fatigue, you need to rest for 5 to 10 minutes after using your eyes for 1 hour, and try not to play video games for more than 40 minutes. Maria levina, ophthalmologist of eyecraft ophthalmology studio in Russia, suggested: "children under 4 years old should not touch electronic products at all; children under 8 years old should not touch electronic products for more than 15 minutes to 20 minutes every day; children over 12 years old should not touch electronic products for more than 2 hours every day." Felix DIAS, former president of the Panamanian Ophthalmology Society, mentioned the "20-20-20" formula, that is, when using electronic equipment, stop looking at the screen for 20 seconds every 20 minutes, and look 20 feet (about 6 meters) away to rest your eyes. The third trick of scientific eye use: increase outdoor activities. Frank Scheffer, an expert at the Institute of Ophthalmology of Tubingen University in Germany, said that the best measure to prevent myopia is to spend enough time outdoors, such as two hours of outdoor activities every day. Myopia usually occurs between the ages of 8 and 15, but the development of the eyes does not end until the age of 16 to 18. At least before that, sufficient sunlight can inhibit the development of myopia. Park Yujing, an ophthalmologist of Gangnam bright world in South Korea, also suggested that we should ensure outdoor activities every day, get more sunshine, and promote the synthesis of vitamin D, so as to prevent myopia. The fourth trick of scientific eye use: regular visual examination. Park Yujing suggested that we should have a visual examination every six months. Christina Garcia, an ophthalmologist at the Martinez Garcia ophthalmic clinic in Panama, recommends regular visual examinations with an interval of 6 months to 1 year. Raul Perez, a doctor at the Cuban Institute of Ophthalmology, also said that children should avoid using electronic screens 1 to 2 hours before going to bed. If conditions permit, they should have an eye examination every year. According to the principal of a school in Quito, the capital of Ecuador, the school has established an alliance with an ophthalmic clinic to conduct an ophthalmic examination for all students and staff every year. (outlook new era)