1997年5月托福阅读全真试题
The experiment was described in a paper presented to the Paris Academy in 1894. Two sequences of twenty photographs each， one from the side and one from behind， show a white cat in the act of righting itself. Grainy and quaint though they are， the photos show that the cat was dropped upside down， with no initial spin， and still landed on its feet Careful analysis of the photos reveals the secret. As the cat rotates the front of its body clockwise， the rear and tail twist counterclockwise， so that the total spin remains zero， in perfect accord with Newton's laws. Halfway down， the cat pulls in its legs before reversing its twist and then extends them again， with the desired end result. The explanation was that while no body can acquire spin without torque， a flexible one can readily change its orientation， or phase. Cats know this instinctively， but scientists could not be sure how it happened until they increased the speed of their perceptions a thousandfold.
31.What does the passage mainly discuss？
（A） The explanation of an interesting phenomenon
（B） Miracles in modern science
（C） Procedures in scientific investigation
（D） The differences between biology and physics.
32.The word "process" in line 10 refers to
（A） the righting of a tumbling cat
（B） the cat's fall slowed down
（C） high-speed photography
（D） a scientific experiment
33.Why are the photographs mentioned in line 16 referred to as an "experiment"？
（A） The photographs were not very clear.
（B） The purpose of the photographs was to explain the process.
（C） The photographer used inferior equipment
（D） The photographer thought the cat might be injured.
34.Which of the following can be inferred about high-speed photography in the late 1800's？
（A） It was a relatively new technology.
（B） The necessary equipment was easy to obtain.
（C） The resulting photographs are difficult to interpret.
（D） It was not fast enough to provide new information.
35.The word "rotates" in line 19 is closest in meaning to
（A） drops
（B） turns
（C） controls
（D） touches
36.According to the passage， a cat is able to right itself in midair because it is
（A） frightened
（B） small
（C） intelligent
（D） flexible
37.The word "readily" in line 24 is closest in meaning to
（A） only
（B） easily
（C） slowly
（D） certainly
38.How did scientists increase "the speed of their perceptions a thousandfold" （lines 25-26）？
（A） By analyzing photographs
（B） By observing a white cat in a dark room
（C） By dropping a cat from a greater height.
（D） By studying Newton's laws of motion.
Question 39-50
The changing profile of a city in the United States is apparent in the shifting definitions used by the United States Bureau of the Census. In 1870 the census officially distinguished the nation's "urban" from its "rural" population for the first time. "Urban population" was defined as persons living in towns of 8，000 inhabitants or more. But after 1900 it meant persons living in incorporated places having 2，500 or more inhabitants.
Then， in 1950 the Census Bureau radically changed its definition of "urban" to take account of the new vagueness of city boundaries. In addition to persons living in incorporated units of 2，500 or more， the census now included those who lived in unincorporated units of that size， and also all persons living in the densely settled urban fringe， including both incor- porated and unincorporated areas located around cities of 50，000 inhabitants or more. Each such unit， conceived as an integrated economic and social unit with a large population nucleus， was named a Standard Metropolitan Statistical Area（SMSA）。
Each SMSA would contain at least （a） one central city with 50，000 inhabitants or more or （b） two cities having shared boundaries and constituting， for general economic and social purposes， a single community with a combined population of at least 50，000， the smaller of which must have a population of at least 15，000. Such an area included the county in which the central city is located， and adjacent counties that are found to be metropolitan in character and economically and socially integrated with the country of the central city. By 1970，about two-thirds of the population of the United States was living in these urbanized areas， and of that figure more than half were living outside the central cities.