English

The past: radio sam, not a bare radio

English "I worked" is one word. Serbian needs two: an -o / -la form plus a helper from "to be". Radio sam, radila sam, radili smo. Without the helper the phrase sounds cut off. For example: “Јуче сам био код лекара” — Yesterday I was at the doctor's. A rule from the Serbian course: worked out on examples, not memorized as a wording.

Updated September 1, 2026 · Lingofly

How it works

English "I worked" is one word. Serbian needs two: an -o / -la form plus a helper from "to be". Radio sam, radila sam, radili smo. Without the helper the phrase sounds cut off.

The masculine form ends in -o: radio, išao, izgubio. The feminine puts the l back: radila, išla. So the past always tells who is speaking.

The helper is a short unstressed word and takes second place. Juče sam radio, and never "Sam juče radio".

Two things turn up at once. Beside se the helper je drops out: pokvarilo se, not "pokvarilo se je". And the negative is one fused word: nisam radio, nije došao.

Table

The past: radio sam, not a bare radio
whothe helperexample
ja (m)samradio sam — I worked (a man speaking)
ja (f)samradila sam — I worked (a woman speaking)
tisiradio si — you worked
on / onajeradio je / radila je — he / she worked
mismoradili smo — we worked
visteradili ste — you (pl.) worked
onisuradili su — they worked
negationnisam, nisi, nije…nisam radio — I did not work

By example

  • Јуче сам био код лекара
    Juče sam bio kod lekara
    Yesterday I was at the doctor's
  • Нисмо добили рачун
    Nismo dobili račun
    We did not get the bill
  • Лифт се покварио прошле недеље
    Lift se pokvario prošle nedelje
    The elevator broke last week

How the rule settles in your head

A rule is not memorized from an explanation. It is memorized from an attempt to use it and a mistake — that is why the app delivers it mixed in with words, not as a separate lesson: it resurfaces exactly where you forgot it.

Frequently asked

The past: how does it work in Serbian?

English "I worked" is one word. Serbian needs two: an -o / -la form plus a helper from "to be". Radio sam, radila sam, radili smo. Without the helper the phrase sounds cut off.

What does it look like in an example sentence Serbian?

“Јуче сам био код лекара” (Juče sam bio kod lekara) — Yesterday I was at the doctor's. A rule is easier to test on sentences like this than to memorize as a wording: what surfaces in conversation is the sentence.

Next

Test the rule on examplesPractice