广播电视英语短句 第 10 课：体重超标-5

This tells her that the teachers were not giving each student enough space to move around safely. 这向她表明了教师们没有给予每个学生足够的空间，以使他们安全活动。

Six activities produced seventy percent of all injuries: running, basketball, football, volleyball, soccer and gymnastics. 6 项活动构成了所有受伤事件中 70% 的比例，它们是：跑步，篮球，足球，排球，橄榄球和体操。

The study appeared online this week in Pediatrics, the journal of the American Academy of Pediatrics. 这项研究于本周刊登在《小儿科》网络版，这是一份美国小儿科学会的杂志。

The researchers say larger class sizes are another possible reason for the increase in injuries. 研究员们也提到大规模的班级也是导致受伤事件增加的另一个原因。

Larger classes can mean less supervision. 大班级意味着较少的管理。

The National Association for Sport and Physical Education says twenty to thirty students in a P.E. class should be the limit. 全美运动与体育教育协会指出，一堂体育课的人数限定应为 20 —— 30 人。