自然增值

例句：

1. 1. The company's stock price has been on a natural increase since the last quarter.
   该公司的股票价格自上一季度以来一直在自然增长。
2. 2. Natural increase is a key factor in determining the population growth rate.
   自然增长是决定人口增长率的关键因素。
3. 3. The government is working to promote natural increase in the population.
   政府正在努力促进人口的自然增长。