Researchers disagree on whether the “use it or lose it” philosophy holds for cognitive (认知的) aging, but there is some evidence that keeping mentally active can slow age-related declines.At Pennsylvania State University, Sherry Willis and her husband, K. Warner Schaie, have studied 5,000 people, some since 1956. People lucky enough to avoid chronic diseases may also fare (过活) better in intellectual function, they find, perhaps because chronic diseases can restrict lifestyle and reduce mental fare better, perhaps because money can buy intellectually stimulating things like travel.Education helps, too, researchers say, perhaps because it instille (灌输) the conviction that you can always learn something new. The Schaie Willis team also has some other observations. Being in a stable marriage with a stimulating spouse, they say, helps maintain intellectual vigor.Flexibility counts, too. People who stay mentally vibrant are often those who do not insist that “they must do things today as they did before,” Schaie says. In neuropsychological (神经心理学的) terms, the ability to see problems in new ways often yields higher scores on tests of mental function. And people satisfied with life also stay more mentally fit, he says.If you find your mental skills sagging, consider working on specific deficits. When Willis gave 5-hour tutorials (辅导课) on inductive reasoning or spatial (空间的) skills to about 200 people whose skills had declined in the previous 14 years, 40 percent regained lost abilities. That advantage held up seven years later when they were re-tested.Other ways to stay sharp, Schaie says, are doing jigsaw puzzles to hone (磨练) visual-spatial skills, working crossword puzzles for verbal skills, playing bridge for memory and simply matching wits at home with players on TV game shows.Finally, remember this. Even though you may lose some mental skills with normal aging, you also gain in one key area: wisdom. The growth of wisdom — loosely defined as the maturation of intellectual abilities that comes with life experiences — continues throughout the 40s, 50s and even 60s.16. In this passage, the author mainly discusses .17. The word “it” in the saying “use it or lose it” (Paragraph 1) refers to .18. According to researchers, which of the following factors affects cognitive aging?19. From this passage we may safely infer that might help prevent mental declines.20. According to the author, all of the following can truly be said about wisdom EXCEPT that .

A.the role of mental stimulation in preventing mental aging B.gradual loss of mental skills with normal aging C.the relationship between mental function and spatial skills D.effective ways to keep intellectual vigor
问题2：
A.brain power B.cognitive development C.mental stimulation D.intellectual function
问题3：
A.Education B.Chronic illness C.Standards of living D.All of the above
问题4：
A.physical exercises B.social interconnections C.rigid daily routines D.a healthy diet
问题5：
A.wisdom may be thought of as a special form of abilities and knowledge completely developed with life experience B.wisdom may still grow even when the process of mental aging has started C.wisdom is superior in importance to mental skills such as inductive reasoning and spatial skills D.wisdom makes up an important part of brain power