一项在全国六大城市2500名中小学生中进行的调查显示,约有27%的少年儿童没有固定睡眠时间,很多少年儿童都是在晚上10时或11时之后才睡觉。参与此项调查的中国青少年研究中心少年儿童研究所所长孙宏艳指出,调查发现,在很多父母看来,不能按时睡觉不是什么坏事,同学们大多是因为写 A survey conducted among 2,500 elementary and middle school students in six major cities in the country revealed that about 27% of children and teenagers do not have a fixed sleep time. Many children and young children do not sleep until 10 or 11pm. Sun Hongyan, director of the China Youth Research Center’s Children and Youth Research Institute, who participated in the survey, pointed out that the survey found that in the eyes of many parents, sleeping on time is not a bad thing. Most of the students are writing because