案例分析题The natives of La Gomera an carry on long-distance conversations by whistling. For ordinary conversation they speak Spanish. But when they need to speak over a distance, and ordinary speech is impossible, they use the silbo, the name of a whistled form of speech. La Gomera is one of the smaller Canary Islands. It is very mountainous, for it was once a volcano. The island is almost circular in shape, with a high peak in the center. From this peak, deep, narrow valleys are separated by rocky ridges. So in spite of the island’s small size, walking from one place to another may be a slow and difficult job. That is why the silbo is so useful to the natives. A message can easily be whistled over a couple of miles, while to travel that same distance on foot might take an hour. A good whistler can be heard and understood five miles away. His whistling can be heard even farther away when conditions are favorable---when there is little or no wind. I was informed that the record is about nine miles. Anyone who has heard a first-class whistler will agree that this figure is quite possible. Not only does a whistle carry father than a shout, but it is easier to understand. When a person shouts, he cannot pronounce his words well. But in whistling, this problem does not exist. If a whistle is heard at all, it will be heard clearly. Many methods of whistling are used at La Gomera. The only one never used is the common lip whistle, because it is not loud enough. Usually a whistler inserts one or two fingers, or a bent finger, into his mouth. He keeps the front of his tongue still, and his lips spread and stiff. With some practice, this method of whistling can make a tone of astonishing loudness and clearness, with great carrying power and a range of about three octaves (八音度). In the eastern part of the island, most whistlers whistle in the upper range. On other parts of the island, they whistle in the lower range. Some whistlers do not use their fingers at all. Instead, they form a curve in the front part of the tongue which touches the upper front teeth. They then use their hands to form a kind of megaphone. There is nothing very unusual about these methods of whistling. Anyone with a good set of teeth can learn in couple of days to produce a noise that sounds much like a steam whistle. The really remarkable thing is that his simple noise can be used as a language. Compared with shouting, whistling has the following features except being ().
A. moreemotional
B. moreeasilyunderstandable
C. abletocarryfarther
D. moredistinctive
列评价方法属于相对评价的有()
A. 排序法
B. 目标管理法
C. 配对比较法
D. 强制分配法
E. 人物比较法
使用指针式万用表检测元器件,下列说法错误的是()。
A. 绝不可在被测电阻带电的情况下用万用表的欧姆档测量电阻
B. 用万用表测量小功率二极管的极性时,两次测量中所测阻值较小时与黑表笔相接的是二极管的正极
C. 检测三极管质量时通常选用万用表欧姆档的R×100Ω或R×1kΩ档
D. 用万用表测量较大容量电容时,指针有较大偏转后逐渐回去,但最后没有回到起始位置,则该电容器内部有断路现象