Section A
47. 系统解析：So many people use the cell phone frequently every day. But (47) surprisinglylittle is certain about the health effects of its use. Manufactures (48) maintain that cell phones meet government standards for safe radio-frequency radiation emission,but enough studies are beginning to document a possible (49)increase in rare brain tumors ( 肿瘤), headaches and behavioral disorders in children to cause concern. So far, the evidenceisn't (50) conclusive_ on whether the use of cell phones (51)contributes to any increased risk of cancer. In a new trial, researchers asked 47 volunteers to (52) participate in a project to measure glucose (葡萄糖 ) consumption in the brain by scanning the brain to see how cells use energy. For both 50-minutescans, the volunteers had a cell phone (53) fixed to each ear.During the first scan, the devices were turned off, but for the second scan, the phone on the right ear was (54) switched on and received a recorded-message call, although the volume was muted (消音 ) so the noise wouldn't bias the results. The results of the second scan showed that the (55) region of the brain nearest to the device had higher rates of glucose consumption than the rest of the brain. The study shows that cell phones can change brain activity, and (56) provides a whole new avenue for scientific inquiry, though it doesn't say anything about whether cell-phone radiation can cause cancer.
【译文】

N。此空需填一个副词。选项中有两个副词，immensely表示“极大的”，surprisingly表示“令人惊讶的”，该句意为：但——，几乎没有人清楚使用手机在健康方面的影响。故选N。
48. 系统解析：H。此空需填一个原形动词。句意为，制造商——手机符合政府安全射频辐射释放标准。maintain“坚持(认为)，坚称”符合此处语境，故选H。derive“源于，得自”，increase“增加，增长”，participate“参与，参加”。

49. 系统解析：G。此空需填一个单数名词。mission“使命，任务”，不符合语境。increase“增加，增长”符合句意，且后文中紧接着提到increased一词，故选G。

50. 系统解析：A。此空需填一个形容词修饰限定evidence。conclusive“令人信服的，确凿的”，符合句意，故选A。该句意为：到目前为止，对于使用手机是否导致癌症的风险增加，证据并不确凿。

51. 系统解析：B。此空需填一个动词的单数三人称形式。contribute t0为固定搭配，意思是“促成……，导致……”，故选B。

52. 系统解析：J。此空需填一个原形动词，表朗“志愿者”和“项目”之间的关系，且须能与介词in搭配使用。Participate in为固定搭配，意思是“参加，参与(某活动)”。故选J。

53. 系统解析：E。此空需填一个动词的过去分词。switched“转换”，不符合此处语境。fixed“固定”，符合句意，故选E。该句意为：志愿者的每一只耳朵上都固定了一部手机。

54. 系统解析：O。此空需填一个动词的过去分词表示被动。所剩选项中符合条件的只有O项。switch on表示“打开，开启”，故选O。

55. 系统解析：M。此空需填一个名词。第二次的扫描结果显示，靠近手机的大脑_______比大脑其他_______的葡萄糖消耗率要高。很明显，只有regions符合句意。故选M。

56. 系统解析：L。此空需填一个动词的单数三人称形式。所剩选项中只有L项符合。provides“提供”，用在此处符合句意，故选L。该句意为：研究还为科学探究提供了一种全新的途径，但是它对手机辐射是否会引发癌症并未作任何说明。

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