This is the 9881st most frequent Catalan word.
mogui
"Move" (subjunctive form of the verb "moure").
Here, 'mogui' is the third-person singular formal imperative form of the verb 'moure', meaning 'to move', used to give a polite command or request.
Si us plau, mogui el llibre cap a la dreta.
Please, move the book to the right.
In this sentence, 'es mogui' is the third-person singular subjunctive form of the reflexive verb 'moure's', indicating a hypothetical or yet-to-happen movement of the train.
Abans que el tren es mogui, tots han d'estar asseguts.
Before the train moves, everyone must be seated.
Here, 'moguis' is the second-person singular subjunctive form of 'moure', denoting a conditional action that may occur.