了 vs 着 (le vs zhe): completion vs ongoing state
了 (le) marks a completed action or a change of state, while 着 (zhe) indicates a continuous state or an action in progress. The core difference is between 'done' and 'still happening' — choose 了 when the action is finished or a new situation has arisen, and 着 when describing a lasting state or parallel activity.
了 and 着 are aspect particles that modify verbs to indicate the temporal status of an action or state. 了 signals that an action has been completed or a new situation has emerged (perfective aspect). 着 indicates that an action is ongoing or a state persists (durative aspect). While 了 focuses on the endpoint or result of a change, 着 emphasizes the continuation or maintenance of a state. They are not interchangeable: using the wrong particle changes the meaning from 'finished' to 'still in progress'.
When to use each
Use 了 to express that an action has been completed, a change of state has occurred, or a new situation exists. It often appears after verbs (verb-le) to indicate completion, or at the end of a sentence (sentence-le) to mark a change. For example, '我吃了饭' means 'I have eaten' – the eating is finished. 了 is also used with adjectives to indicate a new state: '花红了' means 'the flower has become red'.
了 can have both a 'completion' reading (perfective) and a 'currently relevant state' reading (inchoative). The same particle may imply a past action that still matters now, e.g., '他来了' can mean both 'he came' (past) and 'he is here' (present change).
Use 着 to describe an action in progress or a state that continues over time. It attaches directly after the verb (verb-zhe) and often appears in descriptions: '他笑着' means 'he is smiling' – a continuous state. 着 is also used in patterns like 'V1着V2' to indicate that one action occurs while another is ongoing: '他听着音乐吃饭' (he eats while listening to music). It can also indicate posture or holding a position: '站着' (standing), '坐着' (sitting).
着 is not used for momentary actions in progress (e.g., you cannot say *‘他跳着一下’ for 'he jumped once'). It also cannot be used with resultative complements. Unlike English progressive, 着 often describes a static state rather than an action unfolding.
At a glance
| 了 | 着 | |
|---|---|---|
| Core meaning | Completed action / change of state | Ongoing state or action in progress |
| Typical translation | 'have done', 'finished', 'now there is' | 'is doing', 'is in a state of', 'while doing' |
| Use with stative verbs | Rare; 了 implies becoming that state | Common; describes existing state (e.g., 知道着 is incorrect; use 着呢 for emphasis) |
| Negation | 没(有) + verb (no 了): '没吃饭' (haven't eaten) | 没(有) + verb + 着: '没开着门' (the door isn't open) |
| Place in sentence | After verb or at end of sentence | Directly after verb (no other object between) |
| Used with complements? | Yes, with resultative complements: '做完了' (finished doing) | No; resultative complements imply completion, clash with durative |
Examples
- 了我吃了饭。Wǒ chī le fàn.I have eaten (a meal).Completion of eating; cannot use 着 here because 吃 is a completed action.
- 着他吃着饭呢。Tā chī zhe fàn ne.He is eating (a meal) right now.Ongoing action; 了 would mean he already finished eating.
- 了门开了。Mén kāi le.The door opened (or the door is open now).Change of state: door was closed, now open.
- 着门开着呢。Mén kāi zhe ne.The door is open (current state, not a change).Describes the state of being open; 了 would imply the opening action is over.
- 着他站着等了很久。Tā zhàn zhe děng le hěn jiǔ.He stood waiting for a long time.着 after 站 indicates the standing posture continued while waiting; 了 on 等 marks the completion of waiting.
- 了这本书我看了。Zhè běn shū wǒ kàn le.I have read this book.Completion of reading; 着 would mean 'I am reading it' (ongoing).
Common mistakes
- Using 着 for a completed action: *‘我吃着饭了’ for 'I ate' – should use 了 alone.
- Using 了 to describe an ongoing state: *‘他跑了步了’ for 'he is running' – should use 着 or 正在.
- Omitting 着 in patterns like V着V2: *‘他听音乐吃饭’ – should be 听着音乐吃饭.
- Putting 着 after verbs that already imply a state, like *‘知道着’ – instead use 着呢 for emphasis or simply 知道.
- Using 着 with resultative complements: *‘做完了着’ – 着 cannot follow a resultative phrase.
FAQ
- When do I use 了 vs 着 for actions that are happening right now?
- For an action in progress now, use 着 (often with 呢): '我看着书呢' (I am reading a book). Use 了 to say you have finished it: '我看了书' (I have read the book). 了 does not mean 'now'; it signals completion.
- Can I use 了 and 着 together in the same sentence?
- Yes, but they attach to different verbs or appear in different clauses. For example, '他站着等了很久' – 着 marks the standing state, 了 marks the waiting as completed. They cannot both attach directly to the same verb.
- Why is '门开了' sometimes translated as 'the door is open' and not just 'the door opened'?
- Sentence-final 了 can indicate a current relevant state (change has occurred). So 门开了 means the door is now open (as a result of opening). The same sentence can also describe the past event of opening. Context decides.
- Is there a difference between '看着' and '看了'?
- Yes. '看着' means 'is looking at' or 'in the state of looking' (durative). '看了' means 'looked at (completed)' or 'have seen'. For example, '我看了那部电影' = 'I have seen that movie'; '我看着那部电影' = 'I am watching that movie' (sometimes with 呢).