Introduction
了 (le) placed straight after a verb marks the action as completed. It is tempting to call this "past tense", but Chinese has no tenses — 了 marks completion, which can sit in the past, the future, or a condition. Getting this distinction right early saves a lot of confusion later.
Overview
Structure: Subject + Verb + 了 (le) + (Object)
| Pattern | Example | Translation |
|---|---|---|
| S + V + 了 | 我吃了。(Wǒ chī le.) | I've eaten. |
| S + V + 了 + Number + MW + O | 我买了一本书。(Wǒ mǎi le yī běn shū.) | I bought a book. |
| S + V + 了 + O + 了 | 我吃了饭了。(Wǒ chī le fàn le.) | I've already eaten. |
| S + 没(有) + V + O | 我没买书。(Wǒ méi mǎi shū.) | I didn't buy a book. |
| S + V + 了 + O + 吗？ | 你吃了饭吗？(Nǐ chī le fàn ma?) | Have you eaten? |
了1 vs 了2 — two different 了 (le):
- 了1 sits after the verb and marks a completed action: 我吃了饭。(Wǒ chī le fàn.) — I ate.
- 了2 sits at the end of the sentence and marks a new situation or change: 我吃饭了。(Wǒ chī fàn le.) — I've eaten now / something has changed.
- 下雨了。(Xià yǔ le.) — It has started raining. (a change of state, nothing completed)
- Both can appear together: 我吃了饭了。(Wǒ chī le fàn le.) — I have already eaten.
Examples
我吃了面条。
Wǒ chī le miàntiáo.
I ate noodles.
他买了一本书。
Tā mǎi le yī běn shū.
He bought a book.
昨天我看了两个电影。
Zuótiān wǒ kàn le liǎng gè diànyǐng.
I watched two films yesterday.
你吃了饭吗？
Nǐ chī le fàn ma?
Have you eaten?
我没买那件衣服。
Wǒ méi mǎi nà jiàn yīfu.
I didn't buy that piece of clothing.
下课了，我们走吧。
Xiàkè le, wǒmen zǒu ba.
Class is over, let's go.
Usage Notes
- The negation trap: when you negate a completed action, use 没(有) (méi yǒu) and delete 了. 我没吃饭。(Wǒ méi chī fàn.) ✓ ／ 我没吃饭了。(Wǒ méi chī fàn le.) ❌ This is the single most common 了 mistake at HSK 1.
- 了 is not a past-tense marker. 明天下了课我去找你。(Míngtiān xià le kè wǒ qù zhǎo nǐ.) — Tomorrow, after class finishes, I'll come and find you. Completion in the future.
- A bare verb + 了 with a plain object often sounds unfinished: 我吃了饭 (Wǒ chī le fàn) usually needs more. Adding a number or measure word fixes it: 我吃了一碗饭。(Wǒ chī le yī wǎn fàn.) — I ate a bowl of rice.
- Habitual and ongoing actions never take 了: 我每天喝咖啡。(Wǒ měitiān hē kāfēi.) — I drink coffee every day. No 了.
- 了 is always neutral tone (le) in this use, never liǎo.