当空袭已经结束,发出“解除警报”,其特点是?
The list of Coast Stations is republished()in a trilingual. ["every two years","every three years","every year","every four year"]
法国理性主义思潮的代表是() ["孟德斯鸠","笛卡尔","狄德罗"]
从地理位置看,最适合进行地中海内部贸易,但却不适合探索大西洋的国家是() ["意大利","法国","德国"]
卫星固定业务是指利用一个或多个卫星在处于给定位置的()之间的无线电通信业务。 ["基站","地球站","中心站","遥控站"]
焊缝形成过程中,先焊完的焊缝对后焊完的焊缝的收缩有何影响?