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课时提升作业(十四)
必修3 Module 2
Ⅰ. 阅读理解
A
Prolonging human life has increased the size of the human population. Many people alive today would have died of childhood diseases if they had been born 100 years ago. Because more people live longer, there are more people around at any given time. In fact, it is a decrease in death rates, not an increase in birth rates, that has led to the population explosion.
Prolonging human life has also increased the dependency load(抚养负担). In all societies, people who are disabled or too young or too old to work are dependent on the rest of society to provide for them. In hunting and gathering cultures, old people who could not keep up might be left behind to die. In times of famine(饥荒), infants might be allowed to die because they could not survive if their parents starved, but if the parents survived they could have another child. In most contemporary(当代的)societies, people feel a moral responsibility to keep people alive whether they can work or not. We have a great many people today who live past the age at which they want to work or are able to work; we also have rules which require people to retire at a certain age. Unless these people were able to save money for their retirement, somebody else must support them. In America many retired people live on social security checks which are so little that they must live in near poverty. Older people have more illness than young or middle-aged people; unless they have wealth or private or government insurance, they must often“go on welfare”if they have a serious illness.
