I. Introduction: What is IT and THERE?
• Commonly function as pronouns.
[For example]
A : Has anyone seen the newspaper?
B : The last time I saw it, it was in the living room.
In this sentence, it refers to the newspaper.
3) Population Aging
As a result, this combined effect of increasing life expectancy and decreasing fertility causes population aging. Figure 3 shows the proportion of population in the developed and developing county at aged 65. We can know the proportion of elderly is growing worldwide and then, this proportion will be continually increasing in the future.
Figure3. Percentage of World’s Pop