non-linear relationship

例句：

1. 1. The relationship between the two variablesis non-linear.
   这两个变量之间的关系是非直线的。
2. 2. The graph shows a non-linear increase in temperature with altitude.
   图表显示温度随海拔高度的增加呈非线性增长。
3. 3.In physics, a non-linear system is one that does not followa straight line path.
   在物理学中，一个非线性系统是指不遵循直线路径的系统。