substitution solid solution

例句：

1. 1. The substitution of a new material in place of the old one is crucial for the success of the project.
   用新材料替换旧材料对项目的成功至关重要。
2. 2. The substitution of natural resources for synthetic ones is becoming increasingly important in today's society.
   用天然资源替代合成资源在当今社会变得越来越重要。
3. 3. In the field of medicine, the substitution of antibiotics for traditional treatments has revolutionized theway we approach infectious diseases.
   在医学领域，抗生素替代传统治疗方法已经彻底改变了我们对传染病的处理方式。