9．
Do you or someone you know use a mobile phone？
In today's world，many people use a mobile phone especially businessmen and businesswomen．
These people are an important part of the business world and help our economies develop．In fact in some countries even children and the elderly use mobile phones to keep in touch with family and friends．
We know how useful it is to have a mobile phone，but do we know how safe these phones are？Some scientists say that mobile phones could be a risk to our health．So，money is being given to scientific research to find out if mobile phones may be harmful in any way．
What does the future look like？Is a hands-free phone the answer？The idea behind hands-free sets is simple and maybe they are a safer way for people to communicate．The hands-free set has a piece in your ear and a microphone near your mouth which is connected to a wire that goes into your phone．Some scientists think this is a much safer way to use a phone．Some scientists have proved that a mobile phone 10centimetres from your head is far safer than if the headset is right against your ear．
Some reports say that hands-free sets have 95% less radiation（kl）exposure，while other reports say
that hands-free sets expose you to more radiation．
Governments and the mobile phone industry are researching the effects，including：
●the effects of radio waves on blood pressure and the brain，such as the abilities to concentrate，
remember and learn
●the connections between mobile phone use and brain cancer
●long-term effects of mobile phone use，looking at health histories of people who have used mobiles since the 1980s．
They will be looking at both current mobile phones and the new generation of 4G phones．The results
from these studies will help us understand more about the world beyond mobile communications．
Wouldn't it be strange if scientists discovered that mobile phones were too dangerous and we had to stop using them and go back to writing letter and using the normal telephone？
53．The underlined word"concentrate"meansC．
A．feel interested
B．take actions
C．think carefully
D．a(chǎn)nswer quickly
54．From the passage we can knowB．
A．wearing headsets is a safer way when we communicate with mobile phones
B．nobody can tell exactly which is the safer way to use a mobile phone
C．we'd better stop using hands-free sets while scientists are looking at them
D．there is some connections between mobile phone use and some illness
55．The writer thinks that．D
A．it's certain that new technology brings new problems
B．it would be strange if we stop using mobile phones
C．using the normal telephone can avoid the risk from mobile phones
D．we couldn't stop using mobile phones though they might be harmful in any way．
