Breakdown of Nie wiemy, kto powinien podpisać ten wniosek.
nie
no / not
ten
this (m)
kto
who
wiedzieć
to know
Questions & Answers about Nie wiemy, kto powinien podpisać ten wniosek.
Do I always need a comma before kto in sentences like this?
Yes. In English, we just write "We don't know who...", but in Polish, you must always separate the main clause (Nie wiemy) and the indirect question (kto powinien...) with a comma. This punctuation rule applies to all subordinate clauses, including those starting with words like kto, co, gdzie, or czy.
We are the ones who don't know, so why is the word for "should" (powinien) in the singular masculine form?
The sentence has two parts with two different subjects. In the first part, the hidden subject is "we" (my nie wiemy). In the second part, the subject is kto (who). In Polish, the question word kto always acts as a third-person singular masculine subject, so it must be followed by the masculine singular verb form powinien.
Why is podpisać used here instead of the imperfective form podpisywać?
We use the perfective verb podpisać because signing this application is a single, completed action. If you wanted to talk about the continuous or repetitive process of signing applications in general, you would use the imperfective podpisywać.
Why does ten wniosek look like it's in the dictionary form (nominative case) if it is the direct object being signed?