Saying How Long: Duration of an Action

How do you say you slept for eight hours or studied Chinese for three years? In Chinese, the length of time goes in a specific spot: after the verb, not before it. That placement is the whole trick. Once you've got it, you can say how long anything lasted. Here's the pattern.

The basic rule: duration goes after the verb

A time-when phrase (like 明天, "tomorrow") goes before the verb. But a duration phrase (how long something lasts) goes after the verb. This catches a lot of learners, so it's the first thing to lock in.

verb + duration

• 我睡了八个小时。 — I slept for eight hours.
• 他等了半个小时。 — He waited for half an hour.
• 我们休息了十分钟。 — We rested for ten minutes.

Compare the two kinds of time:

• 我三点睡。 — I sleep at three. (time-when, before the verb)
• 我睡了三个小时。 — I slept for three hours. (duration, after the verb)

Same idea of "time," but completely different positions. When in doubt, ask: am I saying when, or how long? "How long" goes after.

Common duration phrases

These are the time-length expressions you'll plug into the slot:

• 一分钟 — one minute
• 半个小时 — half an hour
• 两个小时 — two hours (note 两, not 二)
• 三天 — three days
• 一个星期 — one week
• 两个月 — two months
• 几年 — a few years

Notice that 小时 (hour), 星期 (week), and 月 (month) take 个 in front, while 天 (day), 年 (year), and 分钟 (minute) don't. So it's 两个月 but 三天.

The object problem (sound familiar?)

Just like with the degree complement, the duration wants to sit right after the verb, but so does the object. They collide. The fix is the same: repeat the verb.

(verb + object) + verb + duration

• 我学中文学了三年。 — I studied Chinese for three years.

The verb 学 appears twice: once with its object 中文, once to carry the duration 三年.

There's also a smoother option many speakers prefer: put the duration between the verb and the object, often with 的.

• 我学了三年（的）中文。 — I studied Chinese for three years.

Here the duration 三年 slips in right after 学了, and the object 中文 follows. The 的 is optional. Both this and the verb-repeat version are correct, but this one-verb form is very common and a bit easier to say.

The two 了s: "did" versus "have been doing"

Duration sentences are where the double-了 pattern really shines. Watch the difference:

• 我学了三年中文。 — I studied Chinese for three years. (and stopped)
• 我学了三年中文了。 — I've been studying Chinese for three years. (and still am)

That extra 了 at the end means the action continues up to now. Without it, the studying is over; with it, you're still at it. This is one of the most useful contrasts in the language, and duration sentences are the perfect place to practice it.

• 我在这儿住了五年了。 — I've lived here for five years (and still do).

Negative: how long something didn't happen

To say you haven't done something for a length of time, the duration moves in front of the verb, and you use 没.

• 我三天没睡觉了。 — I haven't slept for three days.
• 他一个星期没来了。 — He hasn't come for a week.

Notice the flip: for "didn't happen for X long," the time goes before the verb, the opposite of the positive pattern. The final 了 keeps that "up to now" feeling.

A quick recap

Duration goes after the verb, which is the opposite of time-when phrases: 我睡了八个小时 ("I slept eight hours"). When there's an object, either repeat the verb (学中文学了三年) or tuck the duration before the object (学了三年中文). Add a final 了 to mean the action is still going (学了三年中文了 = "and still studying"). And for "haven't done it in X time," flip the duration to the front with 没 (三天没睡). Get the placement right and saying how long becomes second nature.