Question

14．The biggest danger facing airlines nowadays may not be a terrorist with a gun，but the man with portable computer in business class．In the last 16 years，pilots have reported well  over 100 incidents that could have been caused by electromagnetic interference  （电磁干扰）．The source of this interference remains not proved，but increasingly，experts are pointing the  blame at portable electronic devices such as portable computers，radio and cassette players  and mobile telephones．
      RTC．A．an organization which advises the aviation  （航空 ）industry，has suggested that all  airlines ban such devices from being used during"critical"stages of flight  particularly take-off and landing．Some experts have gone further，calling for a total ban during all flights．Cur-rently，rules on using these devices are left up to individual airlines．And although some air-lines prevent passengers from using such equipment during take-off and landing，most are un-willing to carry out a total ban，given that many passengers want to work during flight．
     The difficulty is predicting how electromagnetic fields might affect an aircraft's computers．Experts know that portable devices send out radiation which affects those wavelengths which aircraft use for navigation and communication．But，because they have not been able to reproduce these effects in a laboratory．they have no way of knowing whether the interference might be dangerous or not．
     The fact that aircraft may be fragile to interference raises the risk that terrorists may use radio systems in order to damage navigation equipment．As worrying，though，is the passenger who can't hear the instructions to turn off his radio because the music's too loud．
25．What is said about the over 100 aircraft incidents in the past 16 years？D
A．They may have been caused by the damage to-the radio systems．
B．They may have taken place during take-off and landing．
C．They were proved to have been caused by the passengers portable computers．
D．They were suspected to have resulted from electromagnetic interference．
26．Why is it difficult to predict the possible effects of electromagnetic fields on an airplane's computers？C
A．Because it is extremely dangerous to conduct such research on an airplane．
B．Because it remains a mystery what wavelengths are liable to be interfered with．
C．Because research scientists have not been able to produce the same effects in labs．
D．Because experts lack adequate equipment to do such research．
27．Few airlines want to perform a total ban on their passengers using electronic devices becauseB
A．they don't believe there is such a danger as radio interference
B．the harmful effect of electromagnetic interference is yet to be proved
C．most passengers refused to take a plane，which bans the use of radio and cassette players
D．they have other effective safety measures to fall back on
28．The passage is mainly aboutC．
A．a new rule for all airlines
B．the disadvantages of electronic devices
C．a possible cause of aircraft incidents
D．effective safety measures for air flight．

Answer 1

分析 本文介绍了飞机事故的一种可能成因，即便携式电子设备造成的影响．

解答 25．答案D．细节理解题．根据文章第一段第二句in the last 16 years，pilots have reported well over 100 incidents that could have been caused by electromagnetic interference知，他们怀疑是电磁干扰造成的．故选D．
26．答案C．细节理解题．根据文章第三段最后一句But，because they have not been able to reproduce these effects in a laboratory．they have no way of knowing whether the interference might be．dangerous or not．可知，在实验室科学家一直未能产生相同的效果．故选C．
27．答案B．推理判断题．根据文章第三段The difficulty is predicting how electromagnetic fields might affect an aircraft's computers．可知，答案选B．A、C、D三个选项明显在文章中没提到．故选B．
28．答案C．主旨大意题．通读全文可知，本文在讨论便携式电子设备可能对航空事故的影响．故选C．

点评 本文考查日常生活类文章的阅读水平，学生需要认真阅读原文，把握文章大意，对文章脉络有整体的了解，能仔细查找文中细节，并能根据文章内容进行合理的推测判断．