A co-authored article by Dr. Zhang Jiangzhi (Confucius Institute, University of Southampton) and Professor Wang Haifeng (Peking University), titled “On the Substance–Function Relationship between Theoretical Grammar and Grammar for Teaching Chinese as an International Language,” was published in January 2026 in the CSSCI-indexed JILIN UNIVERSITY JOURNAL OF HUMANITIES AND SOCIAL SCIENCES. The study applies the Chinese philosophical concept of ti–yong to grammar research, arguing that theoretical grammar provides the foundation for teaching grammar. An earlier version of this paper was presented at the 2024 International Annual Conference of the British Chinese Language Teaching Association, hosted by the Confucius Institute at Newcastle University. The article offers a unified framework for grammar teaching, curriculum design, and teaching-material development in international Chinese education.