Difficulty in maintaining attention: can’t concentrate on listening and doing homework, easily influenced by the environment; can’t always remember what he’s talking to, doesn’t know what he’s thinking, confused all day long; always reluctant to do homework, delays until he can’t delay any longer before starting, does it very late, often can’t finish it; especially careless, often loses everything; can’t do homework without supervision, needs repeated guidance; one activity is not finished yet and then moves to another one …… Shen Lixiao, Department of Child and Adolescent Health, Shanghai Xinhua Hospital, China Excessive activity: moves hands and feet a lot, or often wriggles in his seat, leaves his seat in the classroom or in other situations where he needs to stay in his seat, runs around or climbs up and down in inappropriate situations, touches this and that, has difficulty playing quietly or engaging in leisure activities; talks too much, often Busy, as if driven by a motor …… Impulsive behavior: often speaks in class without raising his or her hand, or even blurts out answers before the question is finished, and often ends up saying the wrong thing; impatient, wants what he or she wants immediately and has a hard time waiting; often interrupts or interjects into other people’s activities, and in social interactions, at school or in the workplace Bring trouble ……