您要查找的是不是：
- principal surface of accumulation 主堆积面
- 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。
- 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。
- The gas bubbled to the surface of the water. 气体变成气泡升上水面。
- She's been downgraded (from principal) to deputy. 她已(从校长)降为副校长。
- The surface of the liquid gradually crusted over. 液体表面渐渐地结了一层皮。
- Our principal problem is lack of time. 我们的主要问题就是缺少时间。
- A breeze ruffled the surface of the lake. 一阵微风吹皱了湖面。
- 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。
- A wave broke across the surface of the pool. 一个波浪从池水表面掠过。
- John informed the principal against Paul. 约翰向校长告发了保罗。
- The calm water surface is very much like a mirror. 那平静的水面十分象一面镜子。
- Acid had pitted the surface of the silver. 酸把银器的表面腐蚀了。
- 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。
- He is honest only on the surface. 他只是表面诚实而已。
- Rubber is the country's principal export. 橡胶制品是该国主要的出口产品。
- The principal has a very tight schedule. 校长的日程表排得满满的。
