问题 问答题 简答题

画出三相四极双层绕组一路串联接线圆图,只画出U相。

答案

参考答案:

阅读理解与欣赏

阅读下列文章,完成问题。

蜂鸟

  (1)只产于美洲的蜂鸟,是举世闻名的“最小的鸟”。其实,“蜂鸟”是一个泛称。其中也有大有小,最大的和燕子不相上下,最小的则比黄蜂还要小,两者是如此悬殊一一最大的蜂鸟头竟比最小的全身都还大。

  (2)蜂鸟共有五六百种,它们有一个共同的特点,便是羽毛都异常美丽。因为它实在太好看,故有人将一本专门研究蜂鸟的书题名《活宝石》,还有人称蜂鸟为“闪烁的彩虹”。著名自然科学家布封以诗人般的口吻赞美这些小鸟道:“绿宝石、红宝石、黄宝石,一齐在它们的羽毛上闪闪发光”。一位严肃的动物学家,在他的专门著作中,也不得不花些篇幅写道:“提起蜂鸟,不说一两句赞美的话是很困难的。”

  (3)蜂鸟不仅颜色美丽,它飞舞的姿势也伶俐可爱,因而它们又被称为“飞舞的花朵”。蜂鸟的飞舞和一般鸟类不同,和昆虫反而有点近似——不停振动它的双翼。据统计,每分钟可达五百次之多,所以蜂鸟的心脏特别发达。可是它们的躯体又是如此的细小,以致有人怀疑它们的身体怎么能容纳下许多如此复杂而精致的器官。

  (4)由于飞行方式不同,蜂鸟在飞行的时能做出一般鸟类无法做到的精彩表演——朝后飞(距离当然不太长)。当它飞近花的时候,它很快把长长的嘴插入花中,身体在花之上,接着“表演”开始了,它的身体慢慢地向下沉,好像整个身体都赖长嘴支持着似的(实际上是靠翅膀不停地振动)吸饱了花蜜以后,嘴便拔出来,朝后飞一段。接着闪电般不见了,它的飞行速度是那样快,令人目不暇接,它与以善飞而出名的燕子比起来,也并不逊色。蜂鸟的这种特殊的飞行本领,和它的构造有关,按照躯体大小的比例说来,它骨骼中的龙骨突比鹰还要发达。

  (5)蜂鸟以花蜜为食物,但也捕食昆虫。因它在花丛中飞舞采蜜,自然也和蜂、蝶一样能为植物传粉,加上它又能吃害虫,所以有利于植物繁殖。许多人以为蜂鸟之所以名之为蜂鸟,是因为它和蜜蜂一样的为植物传粉。其实,这不过是一个方面,更重要的是它飞行时也发出“嗡嗡”的声音,这声音的来历自然是因为它的双翼在不停地振动,英文叫它“嗡嗡嗡的鸟”(Humming.bindorHummer)便是由于这缘故。

  (6)蜂鸟不仅穿得漂亮,吃得考究,飞得动人,它的住所也异常精巧。虽然大小不等,有的大如酒杯,有的小到手套大姆指也容纳得下,但里面铺的柔软的绒毛,外面包以碧绿的树叶,有人说,就是仙女也愿以蜂鸟的巢作为它们的洞府,可是这比神仙洞府更美妙的巢究竟有多大呢?以“牙买加蜂鸟”为例,直径大概是1.75英寸,比一个火柴盒还小些

  (7)蜂鸟不但会造精巧的巢,还会出人意料地捍卫自己的家园。它们有时将巢建筑在植物叶子的尖端,使猴子的手无所施其技,有时用蜘蛛丝将巢悬挂在岩石上,巢中往往还有一些为增加重量而特地搬来的石子,以防倾覆。印度也有所谓“蜂鸟”,但那是冒牌货。它的正名应为“太阳鸟”,比真蜂鸟大许多,同时也不是印度特产,中国和非洲许多国家都有,不足为奇。

1、文中有一句话十分概括地介绍了蜂鸟的各种特点,这句话是:__________________。

2、根据文意,蜂鸟得名的由来一是_________________,二是_____________________。

3、第六段画线句运用了________、_________等多种说明方法,这样说明的好处是_______________。

4、科普读物除了具有科学性之外,还有趣味性的特点,请结合文章内容简要说明。

____________________________________________________

阅读理解

阅读理解。

     No one knows exactly how many disabled people there are in the world, but estimates suggest the figure

is over 450 million. The number of disabled people in India alone is probably more than double the total

population of Canada.

     In the United Kingdom, about one in ten people have some disability. Disability is not just something that

happens to other people: as we get older, many of us will become less mobile, hard of hearing or have falling

eyesight.

     Disablement can take many forms and occur at any time of life. Some people are born with disabilities.

Many others become disabled as they get older. There are many progressive disabling diseases. The longer

time goes on, the worse they become. Some people are disabled in accidents. Many others may have a period

of disability in the form of a mental illness. All are affected by people's attitude towards them.

     Disabled people face many physical barriers. Next time you go shopping or to work or to visit friends,

imagine how you would manage if you could not get up steps, or onto buses and trains. How would you cope

if you could not see where you were going or could not hear the traffic? But there are other barriers: prejudice

(偏见) can be even harder to break down and ignorance (无知) inevitably represents by far the greatest barrier

of all. It is almost impossible for the able-bodied to fully appreciate what the severely disabled go through, so it

is important to draw attention to these barriers and show that it is the individual person and their ability, not their

disability, that counts.

1. The key word in Paragraph 4 is _____.

A. disability

B. ignorance

C. prejudice

D. barriers

2. The last word of the passage "counts" most probably means _____.

A. being most important

B. being considered

C. being included

D. being numbered

3. Which of the following statements is NOT true according to the passage?

A. Even the able-bodied may lose some of their body functions when they get older.

B. There are about 10 percent disabled persons in the UK.

C. The whole society should pay due attention to the barriers faced by the disabled people.

D. There no longer exists prejudice against the disabled.

4. It can be concluded from the passage that _____.

A. we should try our best to prevent disablement

B. both physical and mental barriers are hard to break down

C. we must take a proper attitude towards the disabled

D. the able-bodied people will never fully understand the disabled