Natural Science



  • prolific 多产的


摄影术的诞生 The Birth of Photography(TPO22 阅读 Passage2 )


  • camera obscura 照相暗盒
  • silvered copper plate 镀银铜板
  • daguerreotype 银版照相法
  • calotype 碘化银纸照相法
  • revolutionary 革命性的
  • authenticity 真实性
  • authe-: truthfulness
  • obsolete 过时的,废弃的
  • portrait 画像
  • emulsions 乳液
  • candid 坦率,坦率 truthful and straightforward; frank.
  • unposed 未摆姿势的
  • cropping 裁剪
  • trimming 修剪
  • imposed 把…强加于
  • accidental 偶然


The rapid technical development of photography—the introduction of lighter and simpler equipment, and of new emulsions that coated photographic plates, film, and paper and enabled images to be made at much faster speeds—hadsome unanticipated consequences.

Lighting 闪电(TPO18 阅读 Passage3 Q1, 100%, 30 mins)


  • Lighting 闪电
  • electrical discharge 放电
  • take place 发生
  • metal flagpole or a tower 金属旗杆或塔
  • attractive tension 吸引张力
  • ice pellets 冰粒
  • ice crystals 冰晶
  • updraft wind currents 上升气流
  • thick 厚度


Lightning is a brilliant flash of light produced by an electrical discharge from a storm cloud. The electrical discharge takes place when the attractive tension between a region of negatively charged particles and a region of positively charged particles becomes so great that the charged particles suddenly rush together. The coming together of the oppositely charged particles neutralizes the electrical tension and releases a tremendous amount of energy, which we see as lightning. The separation of positively and negatively charged particles takes place during the development of the storm cloud.

The Mystery of Yawning(打哈欠 TPO18 阅读 Passage2)


  • yawn n./v. 哈欠
  • empirical(基于经验的): based on, concerned with, or verifiable by observation or experience rather than theory or pure logic. based on observation 经验主义的。基于观察或经验,非纯逻辑。

You have empirical evidence, evidence that is not based on theory, evidence that you can see, you can measure, you can test it physically. So I think that empirical knowledge is much more useful than theoretical knowledge. Experiance is better than theory. It’s possible to verify it by experiment. So I like to teach English empirically by listening and speaking, I don’t like to teach theoretically using grammar. Theories can be tested empirically you make your theory and you make some your real life tests.

Most medicine is empirical, you give somebody a medicine and then you see if they get better.

Maybe statistics is an empirical science. So if something is empirical, it’s based on observasion of real life. It’s not based on theory.

【错题❌】The word “empirical” in the passage is closest in meaning to:D. based on observation

【错题❌】句子插入 This, however, was not the case. 正确答案:【C】 这个比较难理解

Another flaw of the tiredness theory is that yawning does not raise alertness or physiological activity, as the theory would predict. When researchers measured the heart rate, muscle tension and skin conductance of people before, during and after yawning, they did detect some changes in skin conductance following yawning, indicating a slight increase in physiological activity. However, similar changes occurred when the subjects were asked simply to open their mouths or to breathe deeply. Yawning did nothing special to their state of physiological activity. Experiments have also cast serious doubt on the belief that yawning is triggered by a drop in blood oxygen or a rise in blood carbon dioxide. 【A】Volunteers were told to think about yawning while they breathed either normal air, pure oxygen, or an air mixture with an above-normal level of carbon dioxide. 【B】If the theory was correct, breathing air with extra carbon dioxide should have triggered yawning, while breathing pure oxygen should have suppressed yawning. 【C】In fact, neither condition made any difference to the frequency of yawning, which remained constant at about 24 yawns per hour 【D】Another experiment demonstrated that physical exercise, which was sufficiently vigorous to double the rate of breathing, had no effect on the frequency of yawning Again the implication is that yawning has little or nothing to do with oxygen.