【正文】 (緊縮 ) programs to reduce their imports. The result was a sharp drop in farm prices. This period was more disastrous for farmers than earlier times had been, because farmers were no longer selfsufficient. They were paying for machinery, seed, and fertilizer, and they were also buying consumer goods. The prices of the items farmers bought remained constant, while prices they received for their products fell. These developments were made worse by the Great Depression, which began in 1929 and extended throughout the 1939s. In 1929, under President Herbert Hoover, the Federal Farm Board was anized. It established the principle of direct interference with supply and demand, and it represented the first national mitment to provide greater economic stability for farmers. President Hoover39。s successor attached even more importance to this problem. One of the first measures proposed by President Franklin D. Roosevelt when he took office in 1933 was the Agricultural Adjustment Act, which was subsequently passed by Congress. This law gave the Secretary of Agriculture the power to reduce production through voluntary agreements with farmers who were paid to take their land out of use. A deliberate scarcity of farm products was planned in an effort to raise prices. This law was declared unconstitutional by the Supreme Court on the grounds that general taxes were being collected to pay one special group of people. However, new laws were passed immediately that achieved the same result of resting soil and providing floodcontrol measures, but which were based on the principle of soil conservation. The Roosevelt Administration believed that rebuilding the nation39。s soil was in the national interest and was not simply a plan to help farmers at the expense of other citizens. Later the government guaranteed loans to farmers so that they could buy farm machinery, hybrid (雜交 ) grain, and fertilizers. brought about the decline in the demand for American farm products? A) The impact of the Great Depression. B) The shrinking of overseas markets. C) The destruction caused by the First World War. D) The increased exports of European countries. chief concern of the American government in the area of agriculture in the 1920s was ______ . A) to increase farm production B) to establish agricultural laws C) to prevent farmers from going bankrupt D) to promote the mechanization of agriculture Agricultural Adjustment Act encouraged American farmers to ______. A) reduce their scale of production B) make full use of their land C) adjust the prices of their farm products D) be selfsufficient in agricultural production Supreme Court rejected the Agricultural Adjustment Act because it believed that the Act ______. A) might cause greater scarcity of farm products B) didn39。t give the Secretary of Agriculture enough power C) would benefit neither the government nor the farmers D) benefited one group of citizens at the expense of others was claimed that the new laws passed during the Roosevelt Administration were aimed at ______. A) reducing the cost of farmin B) conserving soil in the longterm interest of the nation C) lowering the burden of farmers D) helping farmers without shifling the burden onto other taxpayers Passage Two Questions 26 to 30 are based on the following passage: In the 1950s, the pioneers of artificial intelligence (AI) predicted that, by the end of this century, puters would be conversing with us at work and robots would be performing our housework. But as useful as puters are, they39。re nowhere close to achieving anything remotely resembling these early aspirations f or humanlike behavior. Never mind something as plex as conversation: the most powerful puters struggle to reliably recognize the shape of an object, the most elementary of tasks for a tenmonthold kid. A growing group of AI researchers think they know where the field went wrong . The problem, the scientists say, is that AI has been trying to separate the highest, most abstract levels of thought, like language and mathematics, and to duplicate them with logical, stepbystep programs. A new movement in AI, on the other hand, takes a closer look at the more roundabout way in which nature came up with intelligence. Many of these researchers study evolution and natural adaptation instead of formal logic and conventional puter programs. Rather than digital puters and transistors, some want to work with brain cells and proteins . The results of these early efforts are as promising as they are peculiar, and the new naturebased AI movement is slowly but surely moving to the forefront of the field. Imitating the brain39。s neural (神經的） work is a huge step in the right direction, says puter scientist and biophysicist Michael Conrad, but it still misses an important aspect of natural intelligence. People tend to treat the brain as if it were made up of colorcoded transistors, he explains, but it39。s not simply a clever work of switches. There are lots of important things going on inside the brain cells themselves. Specifically, Conrad believes that many of the brain39。s capabilities stem from the patternrecognition proficiency of the individual molecules that make up each brain cell. The best way to build and artificially intelligent device, he claims, would be to build it around the same sort of molecular skills. Right now, the option that conventional puters and software are fundamentally incapable of matching the processes that take place in the brain remains controversial. But if it proves true, then the efforts of Conrad and his fellow AI rebels could turn out to be the only game in town. author says that the powerful puters of today ______. A) are capable of reliably recognizing the shape of an object B) are close to