Could sending your child to a good school and making sure they do their homework be putting their eyesight in serious danger? That's the concern raised by research that reveals alarmingly strong links between time spent studying hard and childhood short-sightedness - myopia - that can lead to serious eye diseases.

把孩子送进好学校、确保他们做作业，会不会置其于视力之虞呢？这正是研究关心的问题。研究结果堪忧：勤奋学习所花的时间和儿童近视问题有密切关联，近视可能引发严重眼疾。

Myopia causes distant objects to appear blurred¹, while close ones can be seen clearly. It often develops in childhood, with the eyeball starting to elongate², becoming more egg-shaped than spherical³, or the lens becoming too curved, so the light entering the eye is not focused correctly.

近视会引发看远处的事物模糊，而近处的清晰可见。这通常是童年时形成的，眼球逐渐被拉长，变得越发像蛋形而非球形；或者是因为晶状体过度弯曲，进入眼睛的光线无法正确聚焦。

It looks as if schoolwork might be a strong risk factor for myopia in children. In East Asia, where children are often academically hothoused from an early age, the rise in myopia is even greater.

似乎学校作业是引起儿童近视显著的风险因素。在东亚，孩子很小就被圈起来读书，近视眼人数增长更快。

The key to protecting your child may be as simple as ensuring they play outside as much as possible in the school holidays and after school. Children who did a lot of close-up academic work and spent most of their time indoors were more likely to become short-sighted.

保护小孩的关键其实很简单，只要确保他们在课后和假期里的户外活动时间越长越好。近距离的课业多、待在室内时间又长的孩子更有可能近视。

Chinese school designers are busy with the attempt to tackle⁴ their country's rising myopia rate. In Guangdong province, for example, they have constructed bright-light classrooms with walls and ceilings made of see-through plastic. Two years ago, Taiwanese researchers got one school to lock its students out of the classroom during break-time and lunch. As a result, students had 80 minutes more sunlight during the school day.

中国的学校设计师们正忙着试图解决越来越高的近视率。以广东省为例，广东建造了强光教室，墙壁和天花板都是由通透的塑料制成。两年前，台湾的研究人员让一所学校在休息时段和午饭时间把学生锁在教室外面。这样，学生白天上课就多了80分钟的时间接触阳光。