Sentence-final 了 (change of state)

Something's different now

• A second kind of (completed / change)了le sits at the end of the sentence.
• It signals a change: a new situation has arrived.
• to rain下雨xià yǔ(completed / change)了le = "it's (started) raining now."

… (completed / change)了le (new situation)

• Sentence-final (completed / change)了le = "now (it's changed)".

rain下雨xià yǔ了le。

• to rain下雨xià yǔ(completed / change)了le = "it's raining now" (it wasn't before).

Feelings change too

• I / me我wǒto be hungry饿è(completed / change)了le = "I'm hungry now"; he / him他tāto walk走zǒu(completed / change)了le = "he's gone now".

I我wǒhungry饿è了le。

• I / me我wǒto be hungry饿è(completed / change)了le = "I've gotten hungry."

Recap

Read the full reference: HSK 3 grammar — Particles.