危险: dangerous; perilous; risk; peril; danger 短语和例子发出危险信号 send out a danger signal; 冒生命危险 at the risk of one's life; peril one's life; 脱离危险 out of danger; 在危险中 in danger of; in the time of peri
专家: specialist; expert; proficient 短语和例子水稻专家 expert in rice-growing; 外国专家 foreign expert; 外语专家 foreign language expert; 心脏病专家 specialist in heart disease; 眼科专家 ophthalmologist; eye specialist;
联合国: the united nations (u.n.)◇联合国安全理事会 united nations security council; 联合国否决权 veto; 联合国军 armed forces for u.n.; 联合国粮农组织 united nations food and agriculture organization; 联合国贸易和发展会议 united nat
危险物质: dangerous substancehazardous su tanceshazardous substances