"I am walking with my mom."
Translation:Idę z mamą.
Both are correct, but I think "Idę z mamą." is more natural.
In English you use possesives much more often than in Polish. For example:
On myje włosy = He washes his hair (it's more natural than "On myje swoje włosy")
The same with this sentence. You would not say, in English, "I am walking with the mom".
Quite a few other languages (Portuguese and Esperanto I can say for sure) can use 'the' for certain close posessives. "He kissed the mother" is the same as "He kissed his mother", but "He dropped the apple" does not mean "He dropped his apple" because there is no close bond between a man and his fruit.
I guess Polish doesn't bother with any article or possessive at all because they don't have a word for "the"!
"zet" is only when you spell your name, recite alphabet or some "letters" organizaton like ONZ.
As a prepositon z gets attached to next word so it's "zmoją" or "zmamą".
then you click "slow" TTS pronounces each word separately so it cannot attach one to other, and that leads to "zet"s and "wu"s in a middle of the sentence.
When it's used as a word meaning "from" or "with", the word "z" is pronounced as just the "z" sound—just a consonant, no vowels, no other consonants. Just "zzz".
When Duolingo's audio says "zet", that's really an error, I think. It ought to pronounce it as "z", not as "zet". (The name of the letter Z is pronounced "zet", but the word "z" itself is just pronounced "z".)