Question

It's easy to take your hearing for granted until it's too late.

With the wide    16  _ (popular) of digital entertainment products, it is not uncommon to see people wearing headphones and listening to music    17   running in the park or using public transport. And the volume is often    18  loud that people around them can hear the music as well.

However, doctors warn that such behavior can potentially damage    19__ hearing. "Innoisy places, people tend   20 _(turn) the volume up to get the same clarity of sound. Unfortunately, that can damage the hearing   21  people being aware of it," said Feng Yongfeng, chief ENT physician at Beijing Tian'an Hospital.

After Spring Festival, the hospital witnessed    22  slight increase in the number of teenagers coming in with hearing problems,    23  Feng attributed to them wearing headphones at home for long periods during the holiday. Feng said both in-ear and overhead headphones can harm the ears and    24  (advise) against using them for long periods. He said if you do use headphones it is worth  25  (invest) in the highest quality you can afford.

Answer

 popularity

 while

 so

 their

 to turn 

 without

 a

 which

 advised

 investing

【解析】

 popularity  wide后面of前面要接名词，popular的名词为popularity。

 while 指在公园跑步或者坐公交车的时候，经常看见人们带着耳机。While当…时

 so    固定句型so…that…如此…以至于…

 their    这里的their是会损害指上文提及的带着耳机，听着吵闹音乐的人的听力。

 to turn 固定词组tend to do sth倾向于做某事。

 without 句意是指很多了没有意识到这一点。

 a 这里是指有听力问题的人的数量有一些轻微的增加。

 which    非限制性定语从句的关系代词。

 advised  这里指Feng Yongfeng教育人们宾语长时间的用耳机。

 investing  固定句型sth be worth doing某事值得被做。