Mobilephoneshelpuseasilyfindpeopleanywhereatanytime．Amobilephonecanincludemanythings，suchasgames，musicandInternetaccess（互联网接入）．Today，4.6billionpeoplearoundtheworldhavemobilephones，accordingtoCBS

Question

Mobile phones help us easily find people anywhere at any time．A mobile phone can include many things，such as games，music and Internet access（互联网接入）．Today，4.6billion people around the world have mobile phones，according to CBS News．
However，mobile phones may cause cancer，according to the World Health Organization．In a 2010 study，people who used a mobile phone for 10 years or more were more than two times as likely to get brain cancer，according to CNN．
"I think it is a good idea to give the public some kind of warning that long-term exposure（暴露） to radiation （辐射） from your mobile phone could possibly cause cancer，"told Dr Henry Lai．Lai is a scientist of bioengineering（生物工程） at the University（大学） of Washington who has studied radiation for more than 30years．
These suggestions may help you reduce your risk of cancer：
1．Use a headset（耳机） or speaker
Headsets give out much less radiation than phones．Some headsets give out low-level radiation．However，you should take it off your ear when you're not talking to anyone．Using your phone with a speaker will also make it safer．
2．Listen more，talk less
Your phone gives out radiation when you talk or text，but not when you're listening or getting messages．Listening more and talking less can lower the risk of cancer．
3．Hold the phone away from your body
Hold the phone away from your body when you're talking，not against your ear．Also，don't keep it in your pocket．
4．Choose texting over talking
Phones give out less radiation to send texts than to carry a person's voice．Texting also keeps radiation away from your head．
5．Poor signal？Stay off the phone
A poor signal means that the phone needs to give out more radiation to work．Make and take calls when your phone has a strong signal．
28．The study from 2010showed that___．
A．people should use mobile phones for no more than 10years
B．people who don't use mobile phones will not get brain cancer
C．the longer people use mobile phones，the more likely they are to get brain cancer
D．the more mobile phones people have，the more likely they are to get brain cancer
29．Which is NOT true about the suggestions mentioned in the passage？___
A．Some headsets don't give out radiation．
B．It's not good to carry mobile phones in pockets．
C．Texting is better than making phone calls．
D．Don't make calls when the signal is weak．
30．The passage mainly talks about___．
A．the development and advantages of mobile phones
B．the reason why mobile phone radiation causes cancer
C．the best ways to use mobile phones to communicate
D．how to protect ourselves from mobile phone radiation．

Answer 1

28．C细节理解题．根据第二段In a 2010 study，people who used a mobile phone for 10 years or more were more than two times as likely to get brain cancer，according to CNN可知据CNN在2010年的一项研究中，人们使用手机10年或更久的将会得脑癌的数量超过两倍．结合选项第三项正确．故选C
29．A细节理解题．根据第三段Headsets give out much less radiation than phones．Some headsets give out low-level radiation．可知耳机比手机的辐射更少．一些耳机可以降低辐射强度．结合选项，明确第一项不符合短文中提到的建议．故选A
30．D主旨大意题．根据文章内容可知本文主要讲述了手机辐射的危害，我们如何保护自己免受危害，故选D．