| About one-fourth of those who used media the least reported that their grades were mostly average or below. 最少使用媒体学生的四分之一，其成绩大多为平均水平或以下； But that was true of half the heavy media users. 但是，大量使用媒体的半数学生也如此。 So where are the parents? 因此，家长干什么了？ Children who had any rule limiting the use of any kind of media were exposed to an average of about three hours less media a day. 对任何媒体有使用限制规定的青少年，其每天使用媒体的平均时间约少三小时。 But only one-third of children had to follow any rules. 但是，只有三分之一的青少年需遵守规定。 |
