T-S curve

例句：

1. 1.The T-S curve is a mathematical model that describes the relationship between two variables.
   T-S曲线是描述两个变量关系的数学模型。
2. 2.The T-S curve is used to analyze the growth rate of a population.
   T-S曲线用于分析人口的增长速率。
3. 3.The T-S curve is often used in economics to study the behavior of markets.
   T-S曲线在经济学中常用于研究市场的运行行为。