题目内容
Like distance runners on measured course, all of us will move through time in a roughly predictable pattern.
In the first stage of our lives, we develop and grow, reaching toward the top of physical vitality (energy).
After we grow up, however, the body begins a process of gradually wearing out.
A new awareness of physical fitness may help lengthen our years of health and vitality, yet nothing we do will work to stop the unavoidable force of aging.
Most of the changes of aging take place deep inside the body. The lungs become less able to take in oxygen. Powerful muscles gradually lose their strength. The heart loses power and pumps less blood. Bones grow easier to break.
Finally, we meet a stress, a stress that is greater than our physical resistance. Often, it is only a minor accident or chance infection (a disease caused by virus), but this time, it brings life to an end.
In 1932, a classic experiment nearly doubled the lifetime of rats, simply by cutting back the calories (unit for measuring the energy value of food) in their diet. The reason for the effect was then unknown.
Today, at the university of California at
For the first time, the mystery (something that is difficult to understand or to explain) of why we age is being seriously challenged. Scientists in many fields are now making striking and far-reaching discoveries.
An average lifetime lasts 75 years, yet in each of us lies a potential for a longer life. If we could keep the vitality and resistance to disease that we have at age twenty, we would live for 800 years.
68.What does the underlined word “it” refer to?
A.Physical vitality. B.Stress. C.Aging. D.Physical resistance.
69.The author believes the following EXCEPT that .
A.human’s life pattern is predictable
B.physical fitness can’t stop the force of aging
C.human’s lifetime will last longer than 75 years
D.all of the changes of aging take place deep inside the body
70.How did Dr. Paul Seagle lengthen the lifetime of rats in his experiment?
A.By limiting the protein in their diet.
B.By cutting the calories in their diet.
C.By resetting their clock of aging.
D.By keeping their physical fitness.
71.What is probably the best title for the article?
A.Two Great Experiments B.The Mystery of Human Life
C.Ways to lengthen Human Life D.The Breakthrough in the Study of Aging
Louise was 72 years old and she lived by herself.The flint thing she noticed when she came downstairs that Sunday morning Was that her 36 window was open In fact,it was so wide open that she had 37 closing it.Then she realized that things were not in their proper 38 . Finally,when she found her empty 39 on the kitchen table,she realized the awful 40.At first.she didn’t know what to do.Then she decided to 41 her son,Derek.
Derek,s wife Sybil answered the phone,“it's your mother,”she 42 him,coldly.Louise told Derek about the open window, about things being in the wrong places and about the 43 missing from her purse.
“All right,”said Derek,“Don’t 44 anything.I'll be 45 in half an hour.”
Louise 46 and made herself a pot of tea and some toast.Then she went from room to room wondering 47 anything else was missing.
When Derek arrived.he was content to 48 her looking so calm.“Have you rung the 49 ? he asked.“No”? Then I’ll do that straiight away.”So he rang the police.
As it was Sunday. 50 the only detectives were out.However,the police were polite,but vague(含糊的).“We’Il send 51 round as soon as possible,”they said.
Derek telephoned his wire.“I'm not sure when I'll be home,love.”he told her.“I’ve got to 52 for the police.”while Derek and his mother waited,Derek 51 the catches(挂钩)on the windows and locks on the doors.All of them were old and some of the catches hardly 54 at a11.Derek felt 55 .His mother was an old woman,after a11.“I'll have to change all these,”he told her.
36.A.kitchen | B.bedroom | C.washroom | D.bathroom |
37.A.strength | B.trouble | C.reason | D.puzzle |
38.A.positions | B.situations | C.directions | D.places |
39.A.purse | B.vase | C.pot | D.envelope |
40.A.mistake | B. message | C.news | D.truth |
41.A.visit | B.ask | C.ring | D.punish |
42.A.invited | B.informed | C.stated | D.scolded |
43.A.money | B.coin | C.note | D.bill |
44.A.say | B.move | C.touch | D.prepare |
45.A.round | B.here | C.off | D.away |
46.A.sighed | B.relaxed | C.whispered | D.hurried |
47.A.how | B.why | C.if | D.where |
48.A.realize | B.find | C.know | D.sense |
49.A.hospital | B.neighbour | C.police | D.friend |
50.A.generally | B.1uckily | C.considerably | D.unfortunately |
51.A.someone | B.anyone | C.everyone | D.none |
52.A.hope | B.ask | C.wait | D.call |
53.A.tested | B.repaired | C.fixed | D.examined |
54.A.locked | B.worked | C.helped | D.opened |
55.A.excited | B.silly | C.worried | D.guilty |