题目内容：

Though the facts that too many people on earth and a too rapid increase in the number added each year are not in argument, we always begin the discussion of "population as global issue" with what most persons mean like this. It was quite right to compare demographic growth to "a long, thin powder fuse(导火线)that bums steadily and hesitatingly until it finally reaches the charge and explodes".

To understand the current situation, which is characterized by rapid increases in population, it is necessary to understand the history of population trends. Rapid growth is a comparatively recent phenomenon. Looking back at the 8,000 years of demographic history, we find that populations have been virtually stable or growing very slightly for most of human history. For most of our ancestors, life was hard, often nasty, and very short. There was high fertility(生育)in most places, but this was usually balanced by high mortality. For most of human history, it was seldom the case that one in ten persons would live past forty, while infancy and childhood were especially risky periods. Often, societies were in clear danger of extinction because death rates could exceed their birthrates. Thus, the population problem throughout most of history was how to prevent extinction of the human race.

This pattern is important to notice. Not only does it put the current problems of demographic growth into a historical perspective, but it suggests that the cause of rapid increase in population in recent years is not a sudden

enthusiasm for more children, but an improvement in the conditions that traditionally have caused high mortality.

Demographic history can be divided into two major periods: a time of long, slow growth which extended from about 8000 B.C. till approximately 1650 A.D. In the first period of some 9,600 years, the population increased from some 8 million to 500 million in 1650. Between 1650 and 1975, the population has increased from 500 million to more than 4 billion. And the population reached 6.2 billion throughout the world by the year 2000, One way to appreciate this dramatic difference in such abstract numbers is to reduce the time frame to something that is more manageable. Between 8000 B.C. and 1650, an average of only 50,000 persons was being added annually to the world's population, At present, this number is added every six hours. The increase is about 800000,000 persons annually.

1.The underlined word "demographic" in Paragraph l means       .

A. extinction of human

B. statistics of human population

C. death rate of human

D. development of human population

2.Which of the following demographic growth patterns is most similar to the long thin powder fuse?

A. A slow growth for a long time and then a period of rapid, dramatic increase.

B. Too many people on earth and a few rapid increases in the number added each year.

C. A virtually stable or slightly decreasing period and then a sudden explosion of population.

D. A long period when death rates exceed birthrates and then a short period with higher fertility and lower mortality.

3. During the first period of demographic history, societies were often in danger of extinction because       .

A. only one in ten persons could live past 40.

B. our ancestors had little enthusiasm for more children

C. there was higher mortality than fertility in most places

D. it was too dangerous to have babies due to the poor conditions

4.The author of the passage intends to       .

A. warn people against the population explosion in the near future

B. find out the cause of rapid increase in population in recent years

C. present us a brief and clear picture of the demographic growth

D. compare the demographic growth pattern in the past with that after 1650