Expressing completion with "le"

Also known as: verb 了, completed action 了 and perfective aspect 了.

The particle 了 (le) has a lot of uses. One of the most common is to express the completion of an action. This is called aspect, which is not the same as tense. Tense is about when an action happens - past, present or future. Aspect is about whether the action is complete in whatever time frame we're talking about.

Basic Pattern

To indicate completeness with 了 (le), the structure is:

Subj. + Verb + 了 + Obj.

Notice that 了 (le) goes directly after the verb. This 了 (le) is called verb 了 (le).

Examples

• 你 今天 晚上 吃 了 什么？ Nǐ jīntiān wǎnshang chī le shénme? What did you eat tonight?
• 他 买 了 一个 新 手机。 Tā mǎi le yī gè xīn shǒujī. He bought a new cellphone.
• 昨天 晚上 我 看见 了 UFO。 Zuótiān wǎnshang wǒ kànjiàn le UFO. I saw a UFO last night.
• 我 学 了 两 年 中文。Wǒ xué le liǎng nián Zhōngwén. I studied two years of Chinese.
• 今年 夏天 我 跟 我女朋友 去 了 台湾。 Jīnnián xiàtiān wǒ gēn wǒ nánpéngyou qù le Táiwān. I went to Taiwan with my boyfriend this summer.

The examples above indicate a completed action, but they might also seem very similar to a "past tense" in English. To illustrate that 了 (le) can also indicate that one action is completed before another, see the following examples:

• 你 到 了 告诉 我。Nǐ dào le gàosu wǒ. When you have arrived, tell me. (future action)
• 老板 走 了 以后 你们 再 走。 Lǎobǎn zǒu le yǐhòu nǐmen zài zǒu. After the boss has left, you leave. (future action)
• 你 找到 了 给 我 打 电话。 Nǐ zhǎo dào​ le yǐhòu, gěi wǒ dǎ diànhuà. After you find it, give me a call. (future action)
• 你们 吃 了 饭 以后 可以 出去 玩。 Nǐmen chī le fàn yǐhòu kěyǐ chūqù wán. After you finish eating the meal, you can go out to play. (future action)
• 下 了 这 节 课，我 要 问 老师 一些 问题。Xià le zhè jié kè, wǒ yào wèn lǎoshī yīxiē wèntí. After I finish this class, I need to ask the teacher a few questions. (future action)

As you can see, 了 (le) can appear in sentences about the future as well as the past. What's important is whether or not the action has been completed, no matter what time we're talking about. This also means that the verbal 了 (le) can't be used with habitual or continuous actions.

See also

• Expressing experiences with verbs
• Uses of "le"
• Using "guo" with "le"

Sources and further reading

Books

• Basic Patterns of Chinese Grammar (pp. 65-8) →buy
• Chinese: An Essential Grammar, Second Edition (pp. 57-9) →buy
• Integrated Chinese: Level 1, Part 1 (3rd ed) (pp. 137-9, 208) →buy
• Integrated Chinese: Level 2, Part 1 (pp. 11-4) →buy
• Mandarin Chinese: A Functional Reference Grammar (pp. 185-217) →buy
• New Practical Chinese Reader 1 (新实用汉语课本1) (pp. 199-200) →buy
• New Practical Chinese Reader 1 (新实用汉语课本1)(2nd ed) (pp. 226-8) →buy
• New Practical Chinese Reader 2 (新实用汉语课本2) (pp. 16-8) →buy
• 40 Lessons for Basic Chinese Course (基础汉语40课上册） (pp. 156-7)→buy

Websites

• Yale: The Perfective –Le了 Versus The Modal Particle Le了
• East Asia Student: 了 grammar: four kinds of 了 in Mandarin