Fifty volunteers were alphabetically divided into two equal groups, Group A to participate in a 7-week exercise program and Group B to avoid deliberate(深思熟虑的)exercise of any sort during those 7 weeks．On the day before the exercise program began, all 50 men participated in a step-test．This consisted of stepping up and down on a 16-inch bench at 30 steps a minute for 5minutes．One minute after completion of the step-test, the pulse rate of each subject was taken and recorded．This served as the pretest for the experiment．For the next 7 weeks, subjects in the experimental group(Group A)rode a motorcycle for 15 minutes each day．The exercise schedule called for riders to ride relaxed during the first day’s ride, merely holding on the handle bars and foot pedals(脚踏板)as the machine moved．Then, for the next 3 days, they rode relaxed for 50 seconds of each minute, and pushed, pulled, and pedaled actively for 10 seconds of each minute．The ratio(比率)of active riding was increased every few days, so that by the third week it was half of each minute, and by the seventh week the riders were performing 15 solid(连续的)minutes of active riding．
At the end of the 7 weeks the step-test was again given to both groups of subjects, and their pulses taken．The post-exercise pulse rates of subjects in the experimental group were found to have decreased an average of 30 heart beats per minute, with the lowest decrease 28 and the highest decrease 46．the pulse rates of subjects in the control group remained the same or changed no more than 4 beats, with an average difference between the initial and final tests of zero．
(1)
When were pulse rates taken?
[ ]
A．
After every exercise period．
B．
Every day．
C．
After the step-test．
D．
Every time the ratio of active riding was increased．
(2)
The exercise schedule was planned so that the amount of active riding ________．
[ ]
A．
increased every few days
B．
varied from day to day
C．
increased until the third week and then was kept constant
D．
increased every exercise period
(3)
The post-exercise pulse rates of Group B were found on the average to have ________．
“I'm seventy years old, ”says the gray-haired lady proudly to the entertainer at her Community Club dinner．
“Did you hear that, everyone?”says the entertainer．“This lovely lady is just seventy years young!And she doesn't look a day over fifty．”
He has been careful not to use the word“old”．In a society where youth is so admired, old age is often seen as something sad, something to fight against．Americans prefer not to say“old”people．They use the expression“senior citizens”．They do not talk about“old people's”homes, but“retirement”homes．
In fact, the entertainer is not so wrong．Seventy is not very old these days．People in the US are living longer and longer．In 1980, 12 percent of Americans were over sixty-five years old．By 2030,21 percent will be over sixty-five．One reason for this is that families are getting smaller．The average couple now has only 1.8 children．At the same time, improved medical care means that people are living longer．
This change in the age of Americans is going to have serious results．For one thing, medical costs are rising．The government is unable to pay the elderly people's medical bills that have gone up very much．Some old people have to leave hospital“sicker and quicker”than they should, before they are really better．
More fortunate senior citizens, though, who still have good health, want new laws to be passed to allow them to stay at work．In the past, the retirement age was sixty-five, but that is changing now．Older people are stronger and more energetic than ever before．Many of them refuse to stop working just because they have reached a certain age．
There is a change, too, in the way in which elderly people see themselves．Many are no longer happy to accept the gray hair, bald heads, and boring clothes of their own parents．They like to wear younger-looking clothes and bright makeup(化妆品)．American women spend millions of dollars a year on operations to lift their faces and make those ugly wrinkles disappear．Men are prepared to spend even more on operations to plant new hair on their bald spots．It's worth any money to look younger．
(1)
In America people try to avoid using the word“old”because ________．
[ ]
A．
the old age is seen as something that isn't admired
B．
it is now believed to bring bad luck to elderly people
C．
the standard of getting old has changed
D．
the change in the age has caused a healthy problem
(2)
According to the passage, which of the following does NOT describe the American society correctly?
[ ]
A．
People live longer because of improved medical care．
B．
The government finds it difficult to afford the medical bills of the elderly．
C．
People use polite expressions when talking about old age．
D．
The old patients' time in hospital is strictly limited．
(3)
Which of the following is not the result of the changing in the age of Americans?
[ ]
A．
Medical costs are rising．
B．
The family becomes smaller．
C．
The retirement age needs changing．
D．
Elderly people spend a lot on keeping young．
(4)
The underlined word“Many”in the last paragraph refers to ________．
[ ]
A．
American adults
B．
American old people
C．
young Americans
D．
American women
(5)
This passage is most probably taken from ________．
Milk was one of the main foods of people long before history was written．It will probably keep on being one as long as there are animals that give milk．
Even the word “milk”is very old．It comes from Sanskrit(梵文),one of the oldest languages known to man．A very old picture of milking has been found．It was drawn more than five thousand years ago．
In the years long ago, people got their milk from their own animals．But later new inventions made the milk industry a big business．In 1851 Gail Borden found a way to take some of the water out of milk．This made it keep much longer．Four years later, Louis Pasteur introduced a way to kill the bacteria(细菌)in milk．Next, a special milk bottle was made．This was followed by the invention of machines that could fill bottles with milk．
These discoveries had a great effect on the milk industry．They meant that milk could be stored longer．
Some people believe that milk drinking will become less popular than it has been．But remember how long milk has been an important food and think of many ways in which it is useful．It seems safe to say that milk industry will always be important．
(1)
Milk is probably(most possibly)to be a food of ours ________．
[ ]
A．
when there are animals that can give milk
B．
where there are animals that can give milk
C．
if there are animals and people in the world
D．
if we want to eat every day
(2)
The word“milk”comes from ________．
[ ]
A．
China
B．
India
C．
England
D．
Japan
(3)
People got their milk mainly from their own animals ________．
[ ]
A．
a hundred years ago．
B．
fifty years ago
C．
one hundred and forty years ago
D．
before a number of inventions were made
(4)
Milk industry will be always an important one because ________．
[ ]
A．
milk drinking is very popular in the world
B．
milk has been an important food for a long time and is widely used
C．
milk is a food of good taste and there are many cows
D．
milk can be stored(kept)longer and carried to other countries
