Questions & Answers about Moja majka otvara prozor svako jutro.
Because moj (my) has to agree with the noun it describes.
Majka is:
- feminine
- singular
- here in the nominative case (the subject of the sentence)
So moj changes to moja to match it:
- moj brat = my brother
- moja majka = my mother
- moje dete = my child
This kind of agreement is very important in Serbian.
Majka is the subject of the sentence, so it is in the nominative case.
The sentence is about the mother doing the action:
- Moja majka = my mother
- otvara = opens
- prozor = window
Since my mother is the one performing the action, majka stays in the nominative form.
Because prozor is the direct object of otvara (opens), so it should be in the accusative case.