This is the 5705th most frequent Spanish word.
regresen
"Regresen" means "return" or "come back" (used as a command or request in the subjunctive/formal).
Here, "regresen" is used in the subjunctive mood because it follows an expression of hope.
Espero que ellos regresen pronto de su viaje.
I hope they return soon from their trip.
In this sentence, "regresen" is in the subjunctive mood as it is used in a dependent clause following a command.
Diles que regresen antes de que anochezca.
Tell them to return before it gets dark.
"Regresen" is used in the subjunctive mood to express a necessity or importance.