题目

It's late evening．Sun Tian is using her smartphone do her homework．The 15﹣year﹣old girl from Zhejiang uses an app to read Engish articles according to her teachers instructions．These days，it's normal for teachers to give homework on apps．For example，students are asked to practice English or do math exercises．Some teachers also use Wechat chat groups to give homework．Bu now，Zhejiang province is moving io ban（禁止）teachers fom giving homework on mobile apps because they worry about sudents' eyesight．More than 70 percent of middle school students in China are found t折线统计图的特点是，既可以反映 ，更能反映 ．