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. In addition, each word has a few special usages.

再 Expresses 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。Wǒmen xiàcì zài lái ba.We will come here again next time.
• 我 想 再 看 一下。Wǒ xiǎng zài kàn yīxià.I want to take another look.

You need to use 再 for this usage; you can't use 又:

• 请 又 说 一 次。Since it is asking about a future action, you can't use "又"Qǐng yòu shuō yī cì.
• 请 再 说 一 次。Qǐng zài shuō yī cì.Please say it one more time.

再 Can Express "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。Wǒ yào zài kàn yī bù diànyǐng.I want to watch another movie.
• 你 可以 再 做 一 碗 面条 吗 ？Nǐ kěyǐ zài zuò yī wǎn miàntiáo ma?Can you make another bowl of noodles?
• 我 得 又 写 一 篇 作文。Since it is about the future, you can't use "又"Wǒ děi yòu xiě yī piān zuòwén.I have to write another essay.
• 我 要 又 吃 一 块 蛋糕。Since it is about the future, you can't use "又"Wǒ yào yòu chī yī kuài dàngāo.I want to eat another piece of cake.

再 Can Express "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 爬山。Wǒmen xiān zuò zuòyè zài qù páshān.First we'll do our homework, then we'll go hiking in the mountains.
• 我 先 买 房子 再 结婚。Wǒ xiān mǎi fángzi zài jiéhūn.First I'll buy a house, then I'll get married.
• 我们 吃 完 饭 再 看 电影。Wǒmen chī wán fàn zài kàn diànyǐng ba.We'll finish eating, then go see a movie.
• 我们 回家 再 讨论，好 吗？Wǒmen huíjiā zài tǎolùn, hǎo ma?We can discuss it after we get 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.Wǒ yào kàn wán shū yòu shuìjiào.I want to finish reading the book and then go to sleep.
• 你 先 吃饭 又 打 电话 给 父母。"又" does not sequence events.Nǐ xiān chīfàn yòu dǎ diànhuà gěi fùmǔ.You should eat before you call your parents.

又 Expresses 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

Examples

• 你 怎么 又 给 我 打 电话 了，什么事？Nǐ zěnme yòu gěi wǒ dǎ diànhuà le, shénme shì?Why do you keep calling me? What it it?
• 这 个 人 又 来 了。Zhège rén yòu lái le.This guy is here again.
• 他 又 不 来 上课 了，老师 可能 罚 他。Tā yòu bù lái shàngkè le, lǎoshī kěnéng fá tā.He didn't come to class again. The teacher is probably going to punish him.
• 你 为什么 又 看 这 本 书 了？ 你 已经 看 过 了。 Nǐ wèishénme yòu kàn zhè běn shū le? nǐ yǐjīng kàn guò le.Why are you reading that book again？You've already read it.
• 昨天 他 再 看 了 一天 电视 。 "再" is not used for past events.Zuótiān tā zài kàn le yī tiān diànshì.He watched TV all day long again yesterday.
• 昨天 我 再 申请 谷歌 开发 职位 了 。 "再" is not used for past events.Zuótiān wǒ zài shēnqǐng Gǔgē kāifā zhíwèi le.I applied for a developer position at Google again yesterday.

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 + (Aux. +) Verb + Obj.

Examples

• 明天 又 是 星期一 ！ Míngtiān yòu shì Xīngqīyī!Tomorrow is Monday again.
• 明天 又 要 开会，真 烦 人 。 Míngtiān yòu yào kāi huì, zhēn fán rén.We're having another meeting tomorrow. So annoying!
• 你 又 要 辞职 了 ？ 为什么 ？ Nǐ yòu yào cízhí le? wèishénme?You're going to resign again? Why?
• 夏天 快 到 了，又 可以 吃 冰淇淋 了 ！ Xiàtiān kuài dào le, yòu kěyǐ chī bīngqílín le!It's almost summer, and we can eat ice cream again!
• 如果 我 能 瘦 一些，我 就 又 能 穿 我 最 喜欢 的 牛仔裤 啦 ！ Rúguǒ wǒ néng shòu yīxiē, wǒ jiù yòu néng chuān wǒ zuì xǐhuan de niúzǎikù la!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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