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 a certain time frame.
Basic Pattern
To indicate completeness with 了 (le), the structure is:
Notice that 了 (le) goes directly after the verb. This 了 (le) is called verb 了 (le) or 了1.
Examples
- 你 今天 早上 吃 了 什么？ Nǐ jīntiān zǎoshang chī le shénme? What did you eat this morning?
- 他 买 了 一个 新 手机。 Tā mǎi le yī gè xīn shǒujī.He bought a new cell phone.
- 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 Chinese for two years.
- 今年 夏天 我 跟 我 男朋友 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。future actionNǐ dào le gàosu wǒ.When you have arrived, tell me.
- 老板 走 了 以后， 你们 可以 走。 future actionLǎobǎn zǒu le yǐhòu, nǐmen kěyǐ zǒu.After the boss has left, you may leave.
- 你 找到 了 以后 ， 给 我 打 电话。future actionNǐ zhǎodào le yǐhòu, gěi wǒ dǎ diànhuà.After you have found it, give me a call.
- 你们 吃 了 饭 以后 ， 可以 出去 。 future actionNǐmen chī le fàn yǐhòu, kěyǐ chūqù.After you have eaten your food, you can go out.
- 下 了 课 以后 ，我 要 问 老师 一些 问题。future actionXià le kè yǐhòu, wǒ yào wèn lǎoshī yīxiē wèntí.After class is over, I need to ask the teacher a few questions.
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 frame we're talking about. This also means that this 了 (le) isn't used with habitual or continuous actions.
See also
Sources and further reading
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Category:A2 grammar points