On the other hand, it is often pointed out that (39) sustainability limits are near or are reached, there are decreasing productivity gains and people become a cost rather than an asset. If we (40) that there are sustainability limits and that we are close to reaching these limits at a world level, then it is appropriate to check population growth.
A) densityI) developed
B) patterns J) marked
C) generated K) tremendous
D) developing L) effect
E) potentially M) once
F) wonder N) keep
G) frankly O) illustrates
H) assume
Section B（每題2分，20分）
Directions:There are 2 passages in this part. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A), B), C) and D). You should decide on the best choice and mark the corresponding letter on the Answer Sheet with a single line through the center.
Passage One
Questions 41 to 45 are based on the following passage.
There is evidence that the usual variety of high blood pressure is, in part, a familiar disease. Since families have similar genes as well as similar environments, familiar diseases could be due to shared genetic influences, to shared environmental factors, or to both. For some years, the role of one environment factor commonly shared by families, namely dietary salt (i.e., sodium chloride), has been studied at Brookhaven National Laboratory. These studies suggest that long excess salt intake can lead to high blood pressure in man and animals. Some individuals, however, and some rats consume large amounts of salt without developing high blood pressure. No matter how strictly all environmental factors were controlled in these experiments, some salt-fed animals never developed hypertension whereas a few rapidly developed very severe hypertension followed by early death. These marked variations were interpreted to result from differences in genetic constitution.
By mating long successive generations of those animals that failed to develop hypertension from salt intake, a resistant strain (the “R” strain) has been evolved in which consumption of large quantities of salt fails to influence the blood pressure significantly. In contrast, by mating only animals that quickly develop hypertension from salt, sensitive strain (the “S” strain) has also been developed.
The availability of these two strains permits investigations possible. They provide a plausible laboratory model on which to investigate some clinical aspects of the human hypertension. More important, there might be the possibility of developing methods by which genetic susceptibility (敏感性) of human beings to high blood pressure can be defined without waiting for its appearance. Radioactive sodium was an important “tool” in working out the characteristics of the sodium chloride metabolism.
41. The study of the effects of salt on high blood pressure was carried out .
A) as members of the same family tend to use similar amounts of salt
B) because it was proven that salt caused high blood pressure
C) to explore the long-term use of a sodium based substance
D) because of the availability of chemically pure salt and its derivatives
42. The main difference between “S” and “R” rats is their .
A) type of bloodB) need for sodium
C) reaction to saltD) rate of mating
43. It can be inferred from the passage that sodium can be used to .
A) tell the “S” rats from the “R” rats
B) control high blood pressure
C) cure high blood pressure caused by salt
D) determine what a sodium chloride metabolism is like
44. The most beneficial results of the research might be .
A) an early cure for high blood pressure
B) control of genetic agents that cause high blood pressure
C) development of diets free of salt
D) the early identification of potential high blood pressure victims
45. Which of the statements best relates the main idea of this passage?
A) The near future will see a cure for high blood pressure.
B) A tendency toward high blood pressure may be a hereditary factor.
C) The medical field is desperately in need of research.
D) When salt is added rats and human beings react similarly.
Passage Two
Questions 46 to 50 are based on the following passage.
Happiness can be described as a positive mood and a pleasant state of mind. According to recent polls sixty to seventy percent of Americans consider themselves to be moderately happy and one in twenty persons feels very unhappy. Psychologists have been studying the factors that contribute to happiness. It is not predictable nor is a person in an apparently ideal situation necessarily happy. The ideal situation may have little to do with his actual feelings.
A good education and income are usually considered necessary for happiness. Though both may contribute, they are only chief factors if the person is seriously undereducated or actually suffering from lack of physical needs.
The rich are not likely to be happier than the middle-income group or even those with very low incomes. People with college educations are somewhat happier than those who did not graduate from high school, and it is believed that this is mainly because they have more opportunity to control their lives. Yet people with a high income and a college education may be less happy than those with the same income and no college education.
Poor health does not rule out happiness except for the severely disabled or those in pain. Learning to cope with a health problem can contribute to happiness. Those with a good sex life are happier in general, but those who have a loving, affectionate relationship are happier than those who rely on sex alone. Love has a higher correlation with happiness than any other factor.
It should be noted that people quickly get used to what they have, and they are happiest when they feel they are increasing their level no matter where it stands at a given time.
Children whose parents were happily married have happier childhoods are not necessarily happier adults.
The best formula for happiness is to be able to develop the ability to tolerate frustration, to have a personal involvement and commitment, and to develop self-confidence and self-esteem.
46. It can be inferred from the passage that.
A) happiness is predictable
B) a person in an apparently ideal situation must be happy
C) the rich are likely to be happier than the middle-income group
D) happiness is not necessarily connected to one's situation in society
47. People with college education.
A) are not happier than those who have only an education at high school
B) are much happier than those who did not graduate from high school
C) have less opportunity to control their lives
D) have more opportunity to control their lives