3.2 Completed Actions with 了 (le)

The particle 了 (le)

了 (le) after a verb signals a completed action: 我吃了 (wǒ chī le) = I ate / I have eaten. Since verbs don't conjugate, 了 is a key way to mark the past.

With objects

The pattern is often verb + 了 + object: 我买了一本书 (I bought a book). For a simple completed action, 了 can also come at the end of the sentence.

Negation

To negate a completed action, use 没(有) méi(yǒu) and drop 了: 我没吃 (wǒ méi chī) = I didn't eat. Never use 不 for the past.

Key terms

了 (le)

marks a completed action: 我吃了 (I ate)

Pattern

verb + 了 + object: 我买了一本书

Past negation

没(有): 我没吃 (I didn't eat)

不 vs. 没

不 = present/habitual; 没 = completed past

Key idea

verbs don't conjugate; 了 shows completion

Try an AP-style question

"我吃了饭" indicates…

1. a future plan
2. a command
3. a completed action
4. a habit