You may know about"junk food"like chips，hamburgers，cola etc.But do you know about"junk sleep"？
    With the development of health awareness in modern society，students' sleeping time is becoming more and more important.In order to fully understand teenagers' sleep time and the quality of their sleep，some British scientists did a survey about that.Here are the results？
    First of all，the students have too much homework. And parents pay less attention to their sleep.Stress and bad moods also work a lot.What's more，many students play with their cell phones or Ipads after school.The survey found that electronic product in teenagers' bedrooms are mainly affecting（影響） their sleep.Nearly all the teenagers have phones，computers or Ipads in their bedrooms.And many of teenagers have all of them.
    The survey was among 1，000 British children from 12 to 16.It found that one-fifth of them got just 4 to 7 hours of sleep every day in 2020，twice that of 2018.But doctors say they need 8 to 9 hours.Almost 25% of the kids said they fell asleep more than once a week while watching TV，listening to music or using other electronic products.
    The survey found that 40% of the kids felt tired each day."This is very worrying."said Dr.Chris Idzikowski，a British expert."This means you don't get enough sleep and the quality of the sleep is bad.

If

If

you don't get good rest，you can't perform well in school the next day."
（1）What does"junk sleep"mean？（根據(jù)短文內(nèi)容回答問題，10詞以內(nèi)）

Less sleep and the bad quality of sleep.

Less sleep and the bad quality of sleep.

（2）Translate the underlined sentence into Chinese.（請將文中劃線句子翻譯成漢語）

家長很少注意到他們的睡眠問題。

家長很少注意到他們的睡眠問題。

（3）How many children in the survey get 4 to 7 hours' sleep in 2018？

100.

100.

（4）請在文中最后一段的空白處填入一個合適的單詞，使句意完整，邏輯正確。

If

If

（5）According to the passage，please give one piece of advice to the children to help them sleep well.

You had better not play with your cell phones or computer games too much.

You had better not play with your cell phones or computer games too much.