题目内容：
Section ADirections: In this section, there is a short passage with 5 questions or incomplete statements. Read the passage carefully. Then answer the questions or complete the statements in the fewest possible words. Please write your answers on Answer Sheet 2.
Questions12 to16 are based on the following passage.
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 from 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 3000B.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
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