This is the 4649th most frequent Polish word.
musicie
"Musicie" means "you (plural) must" or "you (plural) have to" in English.
Here, 'musicie' is used as the second person plural form of the verb 'musić', meaning 'must' or 'have to', indicating obligation.
Musicie zawsze odrabiać zadanie domowe.
You must always do your homework.
'Musicie' again demonstrates obligation, targeted towards a group being addressed.
Powiedziałem wam, że musicie być gotowi na czas.
I told you (plural) that you must be ready on time.
In this interrogative sentence, 'musicie' is used to query if a group must or needs to perform a certain action.