Passage 2
Many of us believe that a person’s mind becomes less active as he grows older. But this is not true, according to Dr. Jarvik, professor of psychiatry (精神病學(xué)) at the University of California. She has studied the mental functioning of aging persons for several years. For example, one of her studies concerns 136 pairs of identical twins (孿生兒), who were first examined when they were already 60 years old. As Dr. Jarvik continued the study of the twins into their 70s and 80s, their minds did not generally decline as was expected.
However, there was some decline in their psycho-motor speed. This means that it took them longer to accomplish mental tasks than it used to. But when speed was not a factor, they lost very little intellectual ability over the years. In general, Dr. Jarvik’s studies have shown that there is no decline in knowledge or reasoning ability. This is true not only with those in their 30s and 40s, but with those in their 60s and 70s as well.
It is true older people themselves often complain that their memory is not as good as it once was. However, much of what we call "loss of memory" is not that at all. There was usually incomplete learning in the first place. For example, the older person perhaps had trouble hearing, or poor vision, or inattention, or was trying to learn the new thing at too fast a pace. In the cases where the older person’s mind really seems to become less active, it is not necessarily a sign of becoming less active due to old age. Often it is simply a sign of a depressed emotional (壓抑的感情) state.
6. According to Dr. Jarvik’s studies, middle-aged and older persons would expect to __________.
○A. remember less
○B(yǎng). reason better
○C. learn fewer new things
○D. lose no intellectual ability
7. Mental decay due to aging is _________.
○A. common
○B(yǎng). much more common than most people believe
○C. much less common than most people believe
○D. true of those over sixty
8. A long-term study of 136 pairs of twins showed that _________.
○A. they lost a little ability to reason over the years
○B(yǎng). they only factor which decline over the years was their speed with which to perform mental tasks
○C. their memory was not as good as it had once been
○D. their minds became a bit more active as they grew older
9. According to the passage, all the following are instances of "incomplete learning" except _________.
○A. poor hearing
○B(yǎng). bad eyesight
○C. lack of attention
○D. the attempt to learn too many new things
10. What we call mental decay is usually a sign of _________.
○A. a low-spirited state
○B(yǎng). a worsening state of health
○C. old age
○D. nervous tension
Passage 3
For hundreds of years, diseases caused by lack in nutrition (營養(yǎng)) were known to men. Some common nutritional diseases are beriberi (腳氣), and scurvy (壞血病). In the 18th century, James Lind, a Scottish doctor, discovered a cure beriberi - whole rice.
A British scientist in 1906 showed that certain foods contain substances important to the growth and development of the body. In time these substances were called vitamins, meaning essential to life. Today there are 13 known vitamins. The human body produces only three of them.
Vitamins regulate (調(diào)節(jié)) the way the body changes food into energy and living tissues (組織). Each vitamins has a definite use and the lack of one vitamin can interfere with the function of another. The continued lack of one vitamin can cause a vitamin lack disease.
The best way for a healthy person to get vitamins is to eat a balanced diet. Eggs, milk, meat, vegetables, fruits, and whole - grain are the most common sources of the necessary variety of foods.
Vitamins help to speed up certain chemical reactions in the body. These reactions are essential for health. Without vitamins, these reactions would occur very slowly or not at all.
Truly vitamins have been correctly named - essential to good health and life.
11. Men have know about nutritional diseases __________.
○A. a long time
○B(yǎng). in 18th century
○C. recently
○D. in 1906
12. Beriberi is a type of _________.
○A. food
○B(yǎng). vitamin
○C. fruit
○D. disease
13. It takes scientists _______ to know how many vitamins there are.
○A. a long time
○B(yǎng). a few years
○C. a short time
○D. a number of experiments
14. Human body produces __________ kinds of vitamins.
○A. all kinds of
○B(yǎng). five
○C. thirteen
○D. three
15. Eating _______ is the best way to get vitamins.
○A. few things
○B(yǎng). vegetables
○C. fruits
○D. many kinds of food
Many of us believe that a person’s mind becomes less active as he grows older. But this is not true, according to Dr. Jarvik, professor of psychiatry (精神病學(xué)) at the University of California. She has studied the mental functioning of aging persons for several years. For example, one of her studies concerns 136 pairs of identical twins (孿生兒), who were first examined when they were already 60 years old. As Dr. Jarvik continued the study of the twins into their 70s and 80s, their minds did not generally decline as was expected.
However, there was some decline in their psycho-motor speed. This means that it took them longer to accomplish mental tasks than it used to. But when speed was not a factor, they lost very little intellectual ability over the years. In general, Dr. Jarvik’s studies have shown that there is no decline in knowledge or reasoning ability. This is true not only with those in their 30s and 40s, but with those in their 60s and 70s as well.
It is true older people themselves often complain that their memory is not as good as it once was. However, much of what we call "loss of memory" is not that at all. There was usually incomplete learning in the first place. For example, the older person perhaps had trouble hearing, or poor vision, or inattention, or was trying to learn the new thing at too fast a pace. In the cases where the older person’s mind really seems to become less active, it is not necessarily a sign of becoming less active due to old age. Often it is simply a sign of a depressed emotional (壓抑的感情) state.
6. According to Dr. Jarvik’s studies, middle-aged and older persons would expect to __________.
○A. remember less
○B(yǎng). reason better
○C. learn fewer new things
○D. lose no intellectual ability
7. Mental decay due to aging is _________.
○A. common
○B(yǎng). much more common than most people believe
○C. much less common than most people believe
○D. true of those over sixty
8. A long-term study of 136 pairs of twins showed that _________.
○A. they lost a little ability to reason over the years
○B(yǎng). they only factor which decline over the years was their speed with which to perform mental tasks
○C. their memory was not as good as it had once been
○D. their minds became a bit more active as they grew older
9. According to the passage, all the following are instances of "incomplete learning" except _________.
○A. poor hearing
○B(yǎng). bad eyesight
○C. lack of attention
○D. the attempt to learn too many new things
10. What we call mental decay is usually a sign of _________.
○A. a low-spirited state
○B(yǎng). a worsening state of health
○C. old age
○D. nervous tension
Passage 3
For hundreds of years, diseases caused by lack in nutrition (營養(yǎng)) were known to men. Some common nutritional diseases are beriberi (腳氣), and scurvy (壞血病). In the 18th century, James Lind, a Scottish doctor, discovered a cure beriberi - whole rice.
A British scientist in 1906 showed that certain foods contain substances important to the growth and development of the body. In time these substances were called vitamins, meaning essential to life. Today there are 13 known vitamins. The human body produces only three of them.
Vitamins regulate (調(diào)節(jié)) the way the body changes food into energy and living tissues (組織). Each vitamins has a definite use and the lack of one vitamin can interfere with the function of another. The continued lack of one vitamin can cause a vitamin lack disease.
The best way for a healthy person to get vitamins is to eat a balanced diet. Eggs, milk, meat, vegetables, fruits, and whole - grain are the most common sources of the necessary variety of foods.
Vitamins help to speed up certain chemical reactions in the body. These reactions are essential for health. Without vitamins, these reactions would occur very slowly or not at all.
Truly vitamins have been correctly named - essential to good health and life.
11. Men have know about nutritional diseases __________.
○A. a long time
○B(yǎng). in 18th century
○C. recently
○D. in 1906
12. Beriberi is a type of _________.
○A. food
○B(yǎng). vitamin
○C. fruit
○D. disease
13. It takes scientists _______ to know how many vitamins there are.
○A. a long time
○B(yǎng). a few years
○C. a short time
○D. a number of experiments
14. Human body produces __________ kinds of vitamins.
○A. all kinds of
○B(yǎng). five
○C. thirteen
○D. three
15. Eating _______ is the best way to get vitamins.
○A. few things
○B(yǎng). vegetables
○C. fruits
○D. many kinds of food