The human voice, like any sound produced by thrumming a stretched string, has a fundamental frequency. For voice, the centre of that frequency lies mostly below 300Hz depending on the speaker"s sex. Information is conveyed through simultaneous higher-frequency overtones(泛音)and additional components that can stretch up to 20,000 Hz(20kHz). Modern hearing aids are able to distinguish only a small part of that range, typically between 300Hz and 6kHz, reducing noise and amplifying those frequencies where the wearer"s hearing is the weakest. But differentiating elements of many common parts of speech occur in higher frequencies. This is the result both of harmonics(和声)that ripple out from the main tone, and from non-voiced elements used to utter consonants(辅音), which employ the tongue, teeth, cheeks and lips. Take the words "sailing" and "failing". Cut off the higher frequencies and the two are indistinguishable. The problem is compounded on telephone calls, which do not transmit frequencies below 300Hz or above 3.3kHz. People with hearing aids experience this problem constantly, says Brian Moore of the University of Cambridge. Typical hearing loss tends to be most acute at frequencies above 10kHz, which contain quieter sounds but where speech can still include important cues. Older hearing aids cut off at no higher than 6kHz, but much modern equipment stretches this range to 8-10kHz. However, a problem remains, Dr Moore says, because bespoke hearing-aid calibrations for individual users, called "fittings" , do not properly boost the gain of these higher frequencies. So Dr Moore and his colleagues have come up with a better method. Their approach can be applied to many existing devices, and is also being built into some newer ones. A key step in any fitting involves testing an individual"s ability to hear sounds in different frequency bands. Each hearing loss is unique, and for most users a standard profile would be too loud in some ranges and too soft in others. But current tests pay scant attention to the higher frequencies that a device"s tiny speaker can produce, regardless of whether the user needs a boost. Dr Moore"s new test, known as CAM2, which is both a set of specifications and an implementation in software, extends and modifies fittings to include frequencies as high as 10kHz. When the results are used to calibrate a modern hearing aid, the result is greater intelligibility(可懂度)of speech compared with existing alternatives. CAM2 also improves the experience of listening to music, which makes greater use of higher frequencies than speech does.
单选题
Audiphones can help people with hearing problem by______.
【正确答案】
B
【答案解析】解析：根据提干中的audiphones(助听器)定位到首段最后一句的hearing aids(助听器)一处。该题干问：助听器可以通过——帮助有听觉障碍的人。即问的是助听器的工作原理，而原文体现出该问题答案的是首段最后一行：reducing noise and amplifying those frequencieswhere the wearer"s hearing is weakest．意为：减少噪音，放大佩戴者听力最薄弱的那部分频率。四个选项中[C]和[D]两项原文没提到；[A][B]两项与原文较接近。但是选项[A]后半部分的amplifying higher—frequency与原文的amplifying those frequencies where the wearer"s hearing isweakest不符；而选项[B]中的“enhancing certain frequencies加强某段频率”与之相符，故答案为选项[B]。
单选题
Which of the following is true according to Paragraph 2?
【正确答案】
C
【答案解析】解析：选项[A]对应信息是该段最后一句：The problem is compounded on telephone calls，which do not transmit frequencies below 300Hz or above 3．3kHz．由此可见电话只能传递一部分频率，该项中的transmit a wide range of frequencies是错误的。选项[B]在原文没有提到，属于无中生有。选项[C]对应原文这句话:．．．to utter consonants(辅音)，which employ the tongue，teeth，cheeks and lips．意为：发出辅音需要使用舌头、牙齿、脸颊和嘴唇。由此可见该项“人们需要用到嘴巴的多个部分来发出辅音”的表述是正确的。选项[D]对应该段倒数第二句：Cutoff the higher frequencies and the two are indistinguishable．其中“indistinguishable无法区分的”与该项“will not influence understanding不会影响理解”显然是不符的，故该项错误。综上所述，答案为选项[C]。
单选题
We can infer from Paragraph 3 that______.
【正确答案】
C
【答案解析】解析：选项[A]对应该段第二句：Typical hearing loss tends to be most acute at frequenciesabove 10kHz…意为：典型听觉丧失者可能对10千赫兹以上频段最敏感。而该项意为“听觉丧失者什么都听不到”，故该项是错误的。选项[B]原文没有提到，且everything一词过于绝对。选项[C]“现代助听器仍然存在缺陷”可以从该段的“However，a problem remains…”推断出来，故该项正确。选项[D]对应最后两句：So Dr Moore and his colleagues have come up with abetter method．Their approach can be applied to many existing devices，and is also being built intosome newer ones．由此可见，莫尔博士和他的团队是想出新方法，这个方法可以用于现有和新的助听设备上，而不是该项说的“他们发明出新的助听设备”，故该项错误。综上所述，答案为选项[C]。
单选题
According to the text, CAM2 can______.
【正确答案】
A
【答案解析】解析：根据CAM2定位到最后一段。选项[A]对应该段最后一句：CAM2 also improvesthe experience of listening to music．which makes greater use of higher frequencies than speechdoes．意为：CAM2也能增强对音乐的感受力，而音乐比对话使用的高频段更多。由此可以推断CAM2能增强高频，故该项表述正确。选项[B]对应原文“include frequencies as high as10kHz”，原文并没有提到“reach the highest frequency”，故该项错误。选项[C]make speechmore confusing与原文的“greater intelligibility”不符，故错误。选项[D]replace a modern hearingaid也是无中生有，文中提到的CAM2是一个用于助听设备的软件，并不能取代助听器。综上所述，答案为选项[A]。
单选题
The text mainly focuses on modern hearing aid"s ______.