3、    It's difficult to get the young to listen to anything you say these days．They have shut themselves off from the world with earplugs attached to their personal stereos such as MP3 players. And with more than three million iPods and MP3 players sold in Britain every year．it's not just the young who have been in the personal stereo habit．But at what risk is our hearing?

    When MP3 players and iPods are turned to full volume，the sound can reach 104 dB (分貝)，the maximum(最大值)allowed by EU safety standards but almost as loud as a pneumatic drill(氣鉆)(110dB)

    The advice from scientists is to turn down the volume and limit use of such machines to an hour a day；the producers also recommend taking regular breaks to give the ears a rest．Yet research by the Royal National institute for the Deaf (RNID)showed that 39 percent of the young don't practice safe listening. The worry is that they could be creating problems later in life．

    People with good hearing have tiny hair cells that line the inner ear and transmit(傳遞) signals to the brain，which it interprets as sound.  When repeatedly exposed to uncomfortably loud noises(loud is defined as above 80 dB)，including music through headphones and at concerts，those hair cells require a rush of blood or oxygen，otherwise“they effectively die”. Temporary(臨時的)hearing loss or tinnitus(ringing in the ears) is a sign that hair cells are trying to recover，but over time recovery becomes impossible．

    At UK cinemas，sound levels of 110dB have been recorded．Music played in nightclubs is so loud as to be comparable，in some cases，to standing two feet away from an aeroplane as it takes off(110dB)．The level at which pain starts to happen for sound is 140dB．

1．When you use MP3 player，you should do the following except       

    A．turn it to the volume              B．take regular breaks

    C．use it less than an hour a day       D．turn down the volume

2．Which of the following is NOT true?

    A．Young people like their personal stereos such as MP3 players．

    B．More than three million iPods and MP3 players are sold in Britain every year．

    C．It is no doubt that sonic British young people’ s hearing is at risk．

    D．More than 50 percent of the British young people don't practice safe listening.

3．The highest safe sound shouldn't be louder than       

    A．80db            B．140db           C．104db          D．110db

4．What would be the best title for the passage?

    A．A Warning That Fails on Deaf Ears     B．MP3 Players——Hearing Killers

    C．The Causes of Hearing Loss           D．Hair Cells Suffering from Loud Noises