Questions & Answers about Dok ja perem sudove, moja sestra čisti sto.
Here dok means while. It introduces an action happening at the same time as another action.
So:
- Dok ja perem sudove = While I wash/am washing the dishes
- moja sestra čisti sto = my sister cleans/is cleaning the table
In other contexts, dok can also mean until, so you always understand it from the sentence.
Yes, it could be omitted.
Serbian often leaves out subject pronouns because the verb form already shows who is doing the action.
So both are possible:
- Dok ja perem sudove, moja sestra čisti sto.
- Dok perem sudove, moja sestra čisti sto.
Including ja gives a little more emphasis or contrast, something like:
- while I wash the dishes, my sister cleans the table
It is not wrong at all; it just sounds slightly more explicit.
Perem is the 1st person singular present tense of prati/prati se in the sense to wash.
Here is the present tense of prati:
- ja perem = I wash / am washing