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A．He was a brave soldier.B．He took war photographs.C．He painted portraits.D．He designe
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听力原文： Today, I'll be talking about the invention of the camera and photography. The camera is often thought to be a modem invention. But as early as 1727, a German physicist discovered that light darkens silver salt, a chemical compound. Using as a camera, a big box with small hole to let the light in, he made temporary images on the salt. Silver salt is still the base of film today.
Then a French scientist made the first permanent picture by using a special piece of metal sensitized with silver salt. A photograph he made in 1826 still exists. The painter, Daguerre improved on the process by placing common salt on the metal, This was in 1839, the official date of the beginning of photography, but the problem was the printing of the photographs, and it wasn't until other scientists developed the kind of paper we now use, that good printing was possible and photograph became truly modern.
In 1860's, Matthew Bradey was able to take his famous pictures of the American Civil War. In the 20th century, George Eastman of the Untied States simplified film developing, and Dr. Edwin Land invented the so-called "instant" camera with self-developing film. If we say that photography came into existence in 1839 it follows that it has taken more than one hundred years for the camera to reach its present condition of technical refinement.
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A．She fainted due to the effects of some drug.B．She was stopped by a policeman and tre
无机结合料稳定材料击实试验时，首先将风干试样用铁锤捣碎。()
Section B
Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C and D. You should decide on the best choice.
The first two stages in the development of civilized man were probably the invention of primitive weapons and the discovery of fire, although no body knows exactly when he acquired the use of the latter.
The origin of language is also obscure. No doubt it began very gradually. Animals have a few cries that serve as signals, but even the highest apes have not been found able to pronounce words, even with the most intensive professional instruction. The superior brain of man is apparently a necessity for the mastering of speech. When man became sufficiently intelligent, we must suppose that he gradually increased the number of cries for different purposes. It was a great day when he discovered that speech could be used for narrative. There are those who think in this respect picture language preceded oral language. A man could draw a picture on the wall of his cave to show in which direction he had gone, or what prey he hoped to catch. Probably picture language and oral language developed side by side. I am inclined to think that language has been the most important single factor in the development of man.
Two important stages came not so long before the dawn of written history. The first was the domestication of animals; the second was agriculture. Agriculture was a step in human progress to which subsequently there was nothing comparable until our own machine age. Agriculture made possible an immense increase in the number of the human species in the regions where it could be successfully practiced. These were, at first, only those in which nature fertilized the soil after each harvest. Agriculture met with violent resistance [rom the pastoral nomads(游牧民族), but the agricultural way of life prevailed in the end because of the physical comforts it provided.
Another fundamental technical advance was writing, which, like spoken language, developed out of pictures, but as soon as it had reached a certain stage, it was possible to keep records and transmit information to people who were not present when the information was given.
These inventions and discoveries—fire, speech, weapons, domestic animals, agriculture, and writing—made the existence of civilized communities possible. From about 3000 B. C. until the beginning of the Industrial Revolution less than two hundred years ago there was no technical advance comparable to these. During this long period man had time to become accustomed to his technique and to develop the beliefs and political organizations appropriate to it. There was, of course, an immense extension in the area of civilized life. At first it had been confined to the Nile, the Euphrates(幼发拉底河), the Tigris and the Indus, but at the end of the period in question it covered much the greater part of the inhabitable globe. I do not mean to suggest that there was no technical progress during this long time; there was progress—there were even two inventions of very great importance, namely gunpowder and the mariner's compass but neither of these can be compared in their power to such things as speech and writing and agriculture.
Which one of the following was first discovered or invented in human civilization？
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