average life rate

例句：

1. 1. The study found that the average life expectancy for people in their 20s is around 30 years.
   研究发现，20多岁的人的平均预期寿命约为30年。
2. 2.The company's average life span is over 50 years, which is significantly longer than its competitors.
   该公司的平均寿命超过50年，显著高于竞争对手。
3. 3.The average life span of the species has been increasing steadily over the past century.
   该物种的平均寿命在过去一个世纪里稳步上升。