The World Health Organization（WHO） says that 80% of the world's teens（青少年）don't get enough exercise to live healthy lives.The report was based on research done with students aged 11 to 17 in 146 different countries.The WHO has been studying teen activity levels since 2001 and reports that not much has changed since then.
   The WHO says that kids should get at least an hour of exercise every day. （A）This could include walking，running，biking，dancing，playing sports，or many other activities.More and more research is showing that exercise does not just help the body，it can help the brain，too，improving thinking，test scores and school grades.
   One big reason for the lack of（缺乏）activity in today's teens is technology，such as smartphones，computers and TVs.Many teens find it very hard to pull themselves away from their devices，whether they are texting，playing games，or watching videos or movies.
   The WHO warns（告诫）that young people need to do less playing in the digital world，and more playing in the real world.
   Health experts want schools and families to encourage teens to be more active.Teens should take part in sports，either on teams or just playing around in the playground.Exercise can also be built into a school day's activities.For many kids，walking or biking to school is one way to make that happen. （B）Doctors say 60 minutes of exercise each day don't need to be done all at once.They can be broken down into smaller parts，like 20 minutes，three times a day.

（1）What does the underlined word （A） "This" refer to（指的是）？

Getting at least an hour of exercise every day.

Getting at least an hour of exercise every day.

（2）What is the importance of exercise？

Exercise does not just help the body，it can help the brain，too，improving thinking，test scores and school grades.

Exercise does not just help the body，it can help the brain，too，improving thinking，test scores and school grades.

（3）列举文中专家解决青少年运动不足的两种建议.

①Teens should take part in sports，either on teams or just playing around in the playground.
②Exercise can also be built into a school day's activities.

①Teens should take part in sports，either on teams or just playing around in the playground.
②Exercise can also be built into a school day's activities.

（4）Translate the underlined sentence （B）in the last paragraph into Chinese.

医生说，每天60分钟的锻炼不需要一次完成。

医生说，每天60分钟的锻炼不需要一次完成。

（5）As a student，what's your idea about using the smartphone？

I think we should use the smartphone wisely.Don't use the phone on weekdays，we can play it for one hour on weekends.

I think we should use the smartphone wisely.Don't use the phone on weekdays，we can play it for one hour on weekends.