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- Smog,once an urban annoyance,is now recognized as a health risk,and the automobile has been pinpointed as the principal culprit. 烟雾，原先只不过是一桩使城市居民感到烦恼的事，现在则被公认为危害健康的因素。汽车已被确认为损害健康的罪魁祸首。
- Smog, once an urban annoyance, is now recognized as a health risk, and the automobile has been pinpointed as the principal culprit. ??烟尘，原先只不过是一桩使城市居民感到烦恼的事，现在则被公认为危害健康的因素。汽车已被确认为损害健康的罪魁祸首。
- My wages are the principal source of my income. 薪金是我收入的主要来源。
- They surprised the culprit into telling the truth. 他们用出其不意的办法使罪犯吐露实情。
- The culprit will be whipped when he is found. 那个罪犯找到后就要挨鞭子抽打。
- 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。
- The police are now on the scent of the culprit. 警方已获得罪犯的线索。
- 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。
- John informed the principal against Paul. 约翰向校长告发了保罗。
- 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。
- The police followed home the clue and finally caught the culprit. 警察顺着这条线索一追到底，终于抓住了罪犯。
- 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。
- Our school gave a reception to our new principal. 我们学校为新校长举行了欢迎会。
- The principal knew all the students individually. 校长认识每个学生。
