Learn Polish: Nie wiem, gdzie on teraz jest. - I do not know where he is now.

In Polish, to make a sentence negative, you always put the word nie immediately before the verb you are negating. You don't need any helping words like the English 'do', so nie wiem simply means 'I do not know'.

Why is there no Polish word for 'I' in the first part of the sentence?

Polish verbs change their endings depending on who is doing the action. The verb wiem already means 'I know', so you don't need to add the pronoun ja (I). You only include it if you really want to emphasize who is speaking.

I learned the word znam for 'I know'. Why can't I say nie znam here?

Polish has two different verbs for 'to know'. You use wiedzieć (which becomes wiem here) for knowing facts or information, which is often followed by question words like gdzie (where). You use znać (which becomes znam) only when you mean you are familiar with a specific person, place, or object.

Is the comma before gdzie strictly necessary?

Yes! Unlike English, Polish grammar strictly requires a comma before a second clause in a sentence. Whenever you connect a new part of a sentence using words like gdzie (where), co (what), or że (that), you must place a comma right before it.