第一次: first; for the first time发射: launch; radiate; project; di ...第一次发力: first pull第一次发球: first service一次发射: primary emission; single-fire第一次发球员: first server(双打)第一次发球员: first server第一次发球成功率: first serve average第一次发球得分率: first serve point average第一次发球的回球: first return失去第一次发球权: one down; one hand out; one out一次发出: number quantity or set of items supplied and distributed at one time一次发汗: first sweating一次发汗蜡: crude scale一次发球权: one hand二次发射: second emission; secondary emission; secondaryemission二次发射比: secondary emission ratio二次发射管: secondary emission tube; secondary-emission tube二次发射极: dynode; electron mirror二次发射率: secondary emission rate二次发射性: secondary emission characteristic再次发射: rx任何一次发生: any one occurrence {= aoo; a.o.o.; a.o.occ第一次: first; for the first time◇第一次打击 first-strike; 第一次反射 first reflection; 第一次分裂分离 first division segregation; 第一次量子化 first quantization二次发射电子: secondary emission electron; secondary emission photocell