例：While some people are motivated by a need for success, others are motivated by a fear of failure.
当一些人被成功的渴望所驱动的时候，另一些人却被失败的恐惧所驱动着。
As the average age of the population increases, there are more and more old people to care for.
随着人口平均年龄的增长，有越来越多的老年人需要照顾。
