了

RuleVerb + le: marks completion or realization of an action (aspect, not tense).

Curiosity

Chinese verbs do not change for past tense. So how do you tell "ate" from "eat"?

Intuition

了 (le) is not about time but about completion: the action happened and finished. Placed right after the verb, it stamps "this was realized".

Visualization

wo chi fan (I eat) → wo chi le fan (I ate). le attaches after the verb chi to mark completion.

Essence

了 (le) is the perfective aspect. It can even apply to future events meaning "once completed" (xia le ke, once class ends). The negative uses mei(you) and drops le (mei chi).

Examples

我吃了饭。

I ate.

他买了一本书。

He bought a book.

我没吃饭。

I did not eat.

Mini-quiz

Which expresses "I watched a movie"?