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- posterior principal foci [医] 后主焦点
- posterior principal focus 后主焦点
- Focal length The distance between the centre of a lens and its principal focus. 镜头中心与其主焦点的距离。
- posterior principal focal distance 后主焦距, 次焦距
- posterior principal focal length 后主焦距, 后焦距
- The British Sedimentological Research Group (BSRG) is the principal focus point for all aspects of sedimentological research in the UK. 英国沉积学研究组（BSRG）是英国最主要的沉积学研究中心。
- My wages are the principal source of my income. 薪金是我收入的主要来源。
- The principal shareholder ask for a meeting. 主要股东们要求召开会议。
- It is a posterior view of the skull. 这是颅骨背视图。
- The agent spoke on behalf of his principal. 代理人代表他的委托人说话。
- Keys are available on application to the principal. 向校长申请就可得到钥匙。
- She's been downgraded (from principal) to deputy. 她已(从校长)降为副校长。
- Our principal problem is lack of time. 我们的主要问题就是缺少时间。
- She drank in every word of the principal's lecture. 她全神贯注地听校长演讲的字字句句。
- Wind energy is the most mature of the renewable energy technologies and is the business on which UPC Renewables is principally focused. 负责风力发电项目的经济分析；负责管理并完成风力发电项目的预可研及可研；负责项目合作协议的谈判；定期汇报项目开发进展情况；
- The condition of being posterior in location or time. 在后在位置上或时间上较靠后的状况
- John informed the principal against Paul. 约翰向校长告发了保罗。
- Located or occurring posterior to the nose. 鼻后的位于鼻后的，或发生于鼻后的
- The central or principal vein of a leaf. 中脉中心的或主要的叶脉
- The principal discouraged unexcused absences. 校长不准无故缺课。
