1997年5月托福阅读全真试题
Other trends and inventions had also helped make it possible for Americans to vary their daily diets. Growing urban populations created demand that encouraged fruit and vegetable farmers to raise more produce. Railroad refrigerator cars enabled growers and meat packers to ship perishables great distances and to preserve them for longer periods. Thus， by the 1890's， northern city dwellers could enjoy southern and western strawberries， grapes， and tomatoes， previously available for a month at most， for up to six months of the year. In addition， increased use of iceboxes enabled families to store perishables. An easy means of producing ice commercially had been invented I the 1870's， and by 1900 the nation had more than two thousand commercial ice plants， most of which made home deliveries. The icebox became a fixture in most homes and remained so until the mechanized refrigerator replaced it in the 1920's and 1930's.
Almost everyone now had a more diversified diet. Some people continued to eat mainly foods that were heavy in starches or carbohydrates， and not everyone could afford meat. Never- theless， many families could take advantage of previously unavailable fruits， vegetables， and dairy products to achieve more varied fare.
20.What does the passage mainly discuss？
（A） Causes of food spoilage.
（B） Commercial production of ice
（C） Inventions that led to changes in the American diet.
（D） Population movements in the nineteenth century.
21.The phrase "in season" in line 2 refers to
（A） a kind of weather
（B） a particular time of year
（C） an official schedule
（D） a method of flavoring food.
22.The word "prevent" in line 4 is closest in meaning to
（A） estimate
（B） avoid
（C） correct
（D） confine
23.During the 1860's， canned food products were
（A） unavailable in rural areas
（B） shipped in refrigerator cars
（C） available in limited quantities.
（D） A staple part of the American diet.
24.It can be inferred that railroad refrigerator cars came into use
（A） before 1860
（B） before 1890
（C） after 1900
（D） after 1920
25.The word "them" in line 14 refers to
（A） refrigerator cars
（B） perishables
（C） growers
（D） distances
26.The word "fixture" in line 20 is closest in meaning to
（A） luxury item
（B） substance
（C） commonplace object
（D） mechanical device
27.The author implies that in the 1920's and 1930's home deliveries of ice
（A） decreased in number
（B） were on an irregular schedule
（C） increased in cost
（D） occurred only in the summer.
28.The word "Nevertheless" in line 24 is closest in meaning to
（A） therefore
（B） because
（C） occasionally
（D） however
29.Which of the following types of food preservation was NOT mentioned in the passage？
（A） Drying
（B） Canning
（C） Cold storage
（D） Chemical additives.
30.Which of the following statements is supported by the passage？
（A） Tin cans and iceboxes helped to make many foods more widely available.
（B） Commercial ice factories were developed by railroad owners
（C） Most farmers in the United States raised only fruits and vegetables.
（D） People who lived in cities demanded home delivery of foods.
Question 31-38
The ability of falling cats to right themselves in midair and land on their feet has been a source of wonder for ages. Biologists long regarded it as an example of adaptation by natural selection， but for physicists it bordered on the miraculous. Newton's laws of motion assume that the total amount of spin of a body cannot change unless an external torque speeds it up or slows it down. If a cat has no spin when it is released and experiences no external torque， it ought not to be able to twist around as it falls.
In the speed of its execution， the righting of a tumbling cat resembles a magician's trick. The gyrations of the cat in midair are too fast for the human eye to follow， so the process is obscured. Either the eye must be speeded up， or the cat's fall slowed down for the phenomenon to be observed. A century ago the former was accomplished by means of high-speed photography using equipment now available in any pharmacy. But in the nineteenth century the capture on film of a falling cat constituted a scientific experiment.