How to tell the difference between “再 zài” and“又yòu” Uncategory "再zài” and “又yòu” both mean repetition and continuity of an action, but "再zài” refers to something unrealized;“又yòu”refers to something realized. For example: 请再说一遍。Qǐng zài shuō yí biàn. Please say it again. 他又来了。Tā yòu lái le. He came again.