Questions & Answers about Muszę uzasadnić odpowiedź.
Muszę is the 1st person singular present tense form of musieć (to have to / must).
So:
- muszę = I have to / I must
- musisz = you have to
- musi = he/she/it has to
In Polish, the subject pronoun ja (I) is usually omitted, because the verb ending already shows who the subject is. So Muszę by itself already means I must / I have to.
Polish often leaves out subject pronouns when they are clear from the verb form.
- Muszę uzasadnić odpowiedź.
- literally: Must-I justify the answer/answer
Because muszę clearly means I must, adding ja is usually unnecessary.
You can say Ja muszę uzasadnić odpowiedź, but that sounds more emphatic, like:
- I have to justify the answer
- It’s me who has to justify it
So the version without ja is the most neutral and natural.