纲

例句：

1. 1. The teacher gave a brief lecture on the importance of discipline in school.
   老师就纪律在学校的重要性做了简短的演讲。
2. 2. The project's success hinges on its ability to meet the deadline.
   这个项目的成功取决于它能否按时完成。
3. 3. The research paper is organized around the main ideas presented in the introduction.
   这篇研究报告围绕引言中提出的主要观点组织。