Comparing "zai" and "you"

Both 再 (zài) and 又 (yòu) express the repeating of an action and can be roughly translated in English to "again." However, 再 is used to express actions that have not yet occurred (the "future again") and 又 is used for actions that have already occurred (the "past again"). They're not interchangeable.

再 is used to express repetition of an action in the future

再 is used to express something that has already happened and will happen again.

Structure

Subj. + 再 + Verb

Examples

• 我们 下次 再 来 吧。We will come here again next time.
• 我 想 再 看 一下 ，这些 不 够。I want to take a look again.
• 请 再 说 一次。Please say it one more time.
• 请 又 说 一次。Since it is asking about a future action, you can't use "又"

再 can be used to say "another"

Aside from expressing the repetition of an action, 再 can also be used to express the equivalent of the English word "another".

Structure

Subj. + 再 + Verb + Obj.

Note that the "Object" mentioned above is usually also going to have an 一 and a measure word in front of it. You'll see that in the examples below.

Examples

• 我 要 再 看 一部 电影。I am going to watch another movie.
• 我 得 又 写 一篇 作文。Since it is about the future, you can't use "又"
• 你 可以 再 做 一碗 面条 吗。You can make another bowl of noodles.
• 我 要 又 吃 一块 蛋糕。Since it is about the future, you can't use "又"

再 can be used to say "and then"

再 can be used with 先 to express sequential order. (ex. Do this....and then this....) In some cases, 再 can appear by itself to simply mean "and then." While this doesn't sound so easy to confuse with 又, it's actually quite common for intermediate learners to misunderstand this use of 再 as meaning "again," so it's definitely worth mentioning here.

Structure

Subj. + (先) + Action 1 + 再 + Action 2

Examples

• 我们 先 做 作业 再 去 酒吧。First we'll do our work, then we'll go to the bar.
• 我 先 买 房子 再 结婚。First I'll buy a house, then I'll get married.
• 我们 买完 饮料 以后 再 看 电影。After we buy a drink, then we'll go to a movie.
• 我们 回家 再 讨论 好 吗？We discuss it after we go home, OK?
• 我 要 看 完 书 又 睡觉。'"又"can not be used as the action"go to bed" haven't occured yet.
• 你 先 吃饭 又 打 电话 給 父母。"又" does not sequence events.

又 is used to express repetition of an action that has already occurred in the past

又 is used in declarative sentences and describes the simple repetition of actions. This repeated action has already occurred once in the past.

Structure

Subj. + 又 + Verb + 了

Example

• 你 怎么 又 给 我 打 电话，什么事？You keep calling me, what's the matter?
• 这 个 老 男人 又 来 了。This old man came again.
• 他 又 不 来 上课 了，老师 可能 罚 他。He didn't come to class again. The teacher is probably going to punish him.
• 你 为什么 又 看 这本书？ 你 已经 看过 了。Why are you reading that book again？ You already read it.
• 昨天 他 再 喝醉 了"再" is not used for past events.
• 昨天 我 再 看 电影 了"再" is not used for past events.

又 adds emotional coloring to events recurring in the future

又 is sometimes used to express that something that has happened before is going to happen in the immediate future. In this case, it usually appears with 要 (yào), 可以 (kěyǐ), 能 (néng), or 是 (shì). This usage often expresses exasperation or impatience with something happening yet again, but sometimes it's more neutral, or even happy.

Structure

Subj. + 又 + 助动词 / 谓语动词 + Obj.

Example

• 明天 又 要 开会，真 烦 人 。We're having ANOTHER meeting tomorrow. So annoying!
• 你 又 要 辞职 了 ？ 为什么 ？ You're going to resign again? Why?
• 夏天 快 到 了，又 可以 吃 冰淇淋 了 ！ It's almost summer, and we can eat ice cream again!
• 明天 又 是 星期一 ！ Tomorrow is Monday again.
• 如果 我 能 瘦 一些，我 就 又 能 穿 我 最 喜欢 的 牛仔裤 啦 ！ If I can slim down a bit, I can wear my favorite jeans again!

Both 再 and 又 have other uses as well

The comparisons above are the cases where 又 and 再 are most easily confused. This wiki also has other uses of both, however:

• All uses of 又
• All uses of 再

See Also

• Sequencing with "xian" and "zai"
• Again in the future with "zai"
• Again in the past with "you"

Sources and further reading

Books

• HSK Standard Course 3 (pp. 67) Anything Goes (无所不谈) →buy
• Integrated Chinese: Level 2, Part 1 (pp. 157) Anything Goes (无所不谈) →buy
• New Practical Chinese Reader 3 (新实用汉语课本3) (pp. 202) Anything Goes (无所不谈) →buy
• Integrated Chinese: Level 2, Part 1 (pp. 157) Anything Goes (无所不谈) →buy
• Integrated Chinese: Level 2, Part 2 (pp. 288) Anything Goes (无所不谈) →buy
• New Practical Chinese Reader 3 (新实用汉语课本3) (pp. 202) Anything Goes (无所不谈) →buy
• Integrated Chinese: Level 1, Part 1 (3rd ed) (pp. 258-9) Anything Goes (无所不谈) →buy
• Integrated Chinese: Level 2, Part 2 (pp. 19-20) Anything Goes (无所不谈) →buy

Websites

• Yale Chinese Usage Dictionary: Using 再 and 又

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