macro-variable造句

Thereupon , in the 3rd chapter , the characteristics of the ecological systems are discussed and the necessity of aggregation is proposed , then , the method of choosing macro - variables is discussed , and the aggregation method for the systems of ordinary differential equation is proposed . in the 4th and 5th two examples : the model of single population and the model of two populations in different environment are discussed , the method which have proposed in 3rd chapter is implemented in the two examples
同时在第四章和第五章中分别介绍生态系统中的两种情况：单物种的发展模型和两物种在不同环境中竞争的模型，分别介绍了对这两种模型建立过程，并且应用第3章中介绍的方法对上述两种模型进行聚合。然后，对聚合后的聚合模型进行分析，得到聚合模型的稳定状态。
It's difficult to find macro-variable in a sentence. 用macro-variable造句挺难的