Still ongoing: 了…了

Structure Verb + 了 + duration + 了

When an action started in the past and CONTINUES up to now, you put one 了 after the verb and ANOTHER at the end: 我在这儿住了五年了 = "I’ve been living here for five years (and still am)". Without the final 了, 我住了五年 would sound finished ("I lived here for five years"). The final 了 is what adds "… and counting".

Examples

我wǒ在zài这zhè儿r住zhù了le五wǔ年nián了le。
I’ve been living here for five years.
他tā等děng了le一yī个ge小xiǎo时shí了le。
He’s been waiting for an hour.
我wǒ们men认rèn识shi十shí年nián了le。
We’ve known each other for ten years.

Levels are indicative: they follow the standard Chinese Grammar Wiki (AllSet Learning) progression, not an official HSK 3.0 mapping. We never assign levels by eye.

This point and the other 370, with audio on every example, inside Wanyu.